SC TO-I/A

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE TO

Tender Offer Statement under Section 14(d)(1) or 13(e)(1)

of the Securities Exchange Act of 1934

(Amendment No. 3)

HUDSON TECHNOLOGIES, INC.

(Name of Subject Company (Issuer))

HUDSON TECHNOLOGIES, INC.

(Name of Filing Person (Issuer))

Common Stock, $0.01 Par Value Per Share

(Title of Class of Securities)

444144-10-9

(CUSIP Number of Class of Securities

Kevin J. Zugibe

Chairman and Chief Executive Officer

Hudson Technologies, Inc.

275 North Middletown Road

Pearl River, New York 10965

(845) 735-6000

(Name, Address and Telephone Number of person authorized to receive notices

and communications on behalf of filing person)

With a copy to:

Robert J. Mittman, Esq.

Ethan Seer, Esq.

Blank Rome LLP

405 Lexington Avenue

New York, New York 10174

Telephone: (212) 885-5000

Telecopier: (212) 885-5001

CALCULATION OF FILING FEE

Transaction Valuation*	Amount of Filing Fee**
$1,307,488	$41.00

* Estimated for purposes of calculating the amount of the filing fee only, this amount is based on the purchase of 1,167,400 shares of common stock at the tender offer price of $1.12 per share. The fee has been previously paid.

** The amount of the filing fee, calculated in accordance with Rule 0-11 under the Securities Exchange Act of 1934, as amended, equals $30.70 per $1,000,000 of the value of the transaction.

[x] Check the box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration number, or the Form of Schedule and the date of its filing.

Amount Previously Paid:	$41.00	Filing Party:	Hudson Technologies, Inc.
Form or Registration No.:	Schedule TO	Date Filed:	June 29, 2007

ÿ Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the state relates:

o third-party tender offer subject to Rule 14d-1.

x issuer tender offer subject to Rule 13e-4

o going-private transaction subject to Rule 13e-3

o amendment to Schedule 13D under Rule 13d-2

Check the following box if the filing is a final amendment reporting the results of the tender offer: ÿ

INTRODUCTION

This Amendment No. 3 (the “Amendment”) amends and supplements the Tender Offer Statement on Schedule TO originally filed with the Securities and Exchange Commission (the “SEC”) on June 29, 2007 by Hudson Technologies, Inc., a New York corporation (the “Company” or “we”), as amended by Amendment No. 1 to Schedule TO filed with the SEC on July 3, 2007 by the Company (“Amendment No. 1”), as further amended by Amendment No. 2 to Schedule TO filed with the SEC on July 20, 2007 by the Company (“Amendment No. 2”) relating to the Company’s offer to purchase up to 1,167,400 shares of its Common Stock, par value $0.01 per share, at a price of $1.12 per share, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated June 29, 2007 (the “Offer to Purchase”), a copy of which was previously filed as Exhibit (a)(1)(A) to the Company’s Schedule TO, and in the Supplemental Letter of Hudson Technologies, Inc. to eligible participants in the Tender Offer (the “Supplemental Letter”), a copy of which was previously filed with Amendment No. 1 as Exhibit (a)(1)(I) to the Company’s Schedule TO, and in the Letter of Transmittal (the “Letter of Transmittal”), a copy of which was previously filed as Exhibit (a)(1)(B) to the Company’s Schedule TO.

This Amendment to Schedule TO is intended to satisfy the reporting requirements of Rule 13e-4(c)(3) promulgated under the Securities Exchange Act of 1934.

The information in the Offer to Purchase and the related Letter of Transmittal, previously filed with the Schedule TO as Exhibits (a)(1)(A) and (a)(1)(B), respectively, and as amended and supplemented by Amendment No. 1 and the Supplemental Letter filed with Amendment No. 1 as Exhibit (a)(1)(I), and by Amendment No. 2, is incorporated into this Amendment No. 3 by reference in answer to items 1 through 12 of the Schedule TO, except that such information is hereby amended and supplemented to the extent specifically provided herein.

(1) The Offer to Purchase is hereby amended as follows:

(a) The second heading, in all capital letters, on the cover page is amended to read as follows:

“THE TENDER OFFER, PRORATION PERIOD, AND WITHDRAWAL RIGHTS WILL EXPIRE AT 5:00 P.M., EASTERN TIME, ON SEPTEMBER 7, 2007, UNLESS THE TENDER OFFER IS EXTENDED.”

(b) The first paragraph of the answer under the question “How long do I have to tender my shares; can the Tender Offer be extended, amended or terminated?”, on page 5 of the Offer to Purchase, under the Summary Term Sheet, is amended to read as follows:

“You may tender your shares until the Tender Offer expires. The Tender Offer will expire at 5:00 PM, Eastern Time, on September 7, 2007, unless extended (such date and time, as they may be extended, the “Expiration Date” and “Expiration Time,” respectively). See Section 1. If a broker, dealer, commercial bank, trust company or other nominee holds your shares, it is likely the nominee has established an earlier deadline for you to act to instruct the nominee to accept the Tender Offer on your behalf. We urge you to contact your broker, dealer, commercial bank, trust company or other nominee to find out the nominee’s deadline. You have an earlier deadline (three business days prior to the Expiration Date) if you wish to tender shares held in the 401(K) Plan. See the “Letter to Hudson Technologies, Inc. 401(K) Savings Plan Participants” sent separately to each participant of the plan. See Section 3.”

(c) The first paragraph of the answer under the question “How do I tender my shares?”, on page 8 of the Offer to Purchase, under the Summary Term Sheet, is amended to read as follows:

“If you want to tender all or part of your shares, you must do one of the following before 5:00 PM, Eastern Time, on September 7, 2007, or any later time and date to which the Tender Offer may be extended, or earlier as described below as required for participants in the 401(K) Plan or as your broker or other nominee may require: …”

(d) The answer under the question “Once I have tenders shares in the Tender Offer, can I withdraw my tender?”, on page 9 of the Offer to Purchase, under the Summary Term Sheet, is amended to read as follows:

“You may withdraw any shares you have tendered at any time before 5:00 P.M., Eastern Time, on September 7, 2007, unless we extend the Tender Offer, in which case you can withdraw your shares until the expiration of the Tender Offer as extended. If we have not accepted for payment the shares you have tendered to us, you may also withdraw your shares at any time after 5:00 P.M, Eastern Time, on September 7, 2007. See Section 4. “

(e) The second paragraph of the Introduction, on page 13 of the Offer to Purchase, is amended to read as follows:

“The Tender Offer will expire at 5:00 PM, Eastern Time, on September 7, 2007, unless extended as described in Section 15.”

(f) The second paragraph of Section 1 of the Offer to Purchase, on page 14, is amended to read as follows:

“The term “Expiration Time” means 5:00 PM, Eastern Time, on September 7, 2007, unless we, in our sole discretion, extend the period of time during which the Tender Offer will remain open, in which event the term “Expiration Time” shall refer to the latest time and date at which the Tender Offer, as so extended by us, shall expire. See Section 15 for a description of our right to extend, delay, terminate or amend the Tender Offer.”

(g) The first paragraph of Section 4 of the Offer to Purchase, on page 22, is amended to read as follows:

“Except as this Section 4 otherwise provides, tenders of shares are irrevocable. You may withdraw shares that you have previously tendered in the Tender Offer according to the procedures described below at any time prior to the Expiration Time for all shares. You may also withdraw your previously tendered shares at any time after 5:00 P.M., Eastern Time, on September 7, 2007 unless such shares have been accepted for payment as provided in the Tender Offer.”

(2) The Offer to Purchase is also hereby amended as follows:

(a) The second bullet point under the question “What happens if more than 1,167,400 shares are tendered at the purchase price?”, on page 8 of the Offer to Purchase, under the Summary Term Sheet, is amended to read as follows:

“second, from all other shareholders who properly tender up to 100% of all of their shares in the Tender Offer and who do not properly withdraw them before the Expiration Time, on a pro rata basis (except for shareholders who tendered shares conditionally for which the condition was not satisfied).”

(b) The answer under the question “If I own more than 100 shares, how many shares may I tender, and will I be subject to proration?”, on page 9 of the Offer to Purchase, under the Summary Term Sheet, is amended to read as follows:

“If you own beneficially or of record more than 100 shares, you may tender up to 100% of these shares. If you properly tender up to 100% of your shares and do not properly withdraw them before the Expiration Time, we will purchase all of your shares tendered and eligible on a pro rata basis (except for shareholders who tendered shares conditionally for which the condition was not satisfied). See Section 1.”

(c) The first paragraph of Section 1 of the Offer to Purchase, on page 14, is amended to read as follows:

“General. Upon the terms and subject to the conditions of the Tender Offer, we will purchase up to 1,167,400 shares of our Common Stock, or if fewer shares are properly tendered, all shares that are properly tendered and not properly withdrawn in accordance with Section 4, at a price of $1.12 per share, net to the seller in cash, less any applicable withholding tax and without interest..”

(d) In Section 1, under the subheading “Priority of Purchases” on page 15 of the Offer to Purchase, the second primary bullet point is amended to read as follows:

“Second, subject to the conditional tender provisions described in Section 6, we will purchase up to 100% of the shares owned by all other shareholders from such other shareholders who properly tender up to 100% of all of their shares, on a pro rata basis with appropriate adjustments to avoid purchases of fractional shares, as described below.”

(e) In Section 1, the second paragraph under the subheading “Proration” on page 16 of the Offer to Purchase, is amended to read as follows:

“We will purchase up to 100% of the total shares held in the name of or beneficially owned by any shareholder in the aggregate.”

SIGNATURE

After due inquiry, and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

HUDSON TECHNOLOGIES, INC.

/s/ Stephen P. Mandracchia

Name: Stephen P. Mandracchia

Title:   Vice President Legal & Regulatory

Date: August 7, 2007

INDEX TO EXHIBITS

Exhibit No. Description

(a)(1)(A)* Offer to Purchase, dated June 29, 2007

(a)(1)(B)* Form of Letter of Transmittal

(a)(1)(C)* Form of Letter to Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees

(a)(1)(D)* Form of Letter to Clients

(a)(1)(E)* Form of Letter to Hudson Technologies, Inc. 401(K) Participants

(a)(1)(F)* Notice of Guaranteed Delivery

(a)(1)(G)* Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9

(a)(1)(H)* Press Release dated June 29, 2007

(a)(1)(I)** Supplemental Letter of Hudson Technologies, Inc., to eligible participants in the Tender Offer

(a)(1)(J) Form of Amended Letter of Transmittal

(a)(1)(K) Form of Amended Letter to Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees

(a)(1)(L) Form of Amended Letter to Clients

(a)(1)(M) Form of Amended Letter to Hudson Technologies, Inc. 401(K) Participants

(a)(1)(N) Form of Amended Notice of Guaranteed Delivery

(a)(1)(O) Second Supplemental Letter of Hudson Technologies, Inc., to eligible participants in the Tender Offer

(a)(1)(P) Press Release dated August 7, 2007

(b)(1)* Amended and Restated Loan Agreement, dated June 26, 2007, between Hudson Technologies, Inc. and Keltic Financial Partners, L.P.

(b)(2)* Mortgage and Security Agreement, dated June 26, 2007, between Hudson Technologies, Inc. and Keltic Financial Partners, L.P.

(b)(3)* Amended and Restated Revolving Note, dated June 26, 2007

(b)(4)* Amended and Restated Term Note A, dated June 26, 2007

(b)(5)* Term Note B, dated June 26, 2007

(c) Not Applicable

(d) Not Applicable

(e)(1)* Stock Purchase Agreement between Hudson Technologies, Inc. and Flemings Funds, dated June 28, 2007

(e)(2)* Stock Purchase Agreement between Fleming Funds and Kevin J. Zugibe, dated June 28, 2007

(e)(3)* Stock Purchase Agreement between Fleming Funds and Stephen P. Mandracchia, dated June 28, 2007

(e)(4)* Stock Purchase Agreement between Fleming Funds and Brian F. Coleman, dated June 28, 2007

(e)(5)* Stock Purchase Agreement between Fleming Funds and James R. Buscemi, dated June 28, 2007

(e)(6)* Stock Purchase Agreement between Fleming Funds and Joseph Longo, dated June 28, 2007

(f) Not Applicable

(g) Not Applicable

(h) Not Applicable

_______________

* Previously filed with the initial Schedule TO as filed with the SEC on June 29, 2007.

** Previously filed with Amendment No. 1 to Schedule TO, as filed with the SEC on July 3, 2007.

EX-99.(A)(1)(J)

Exhibit (a)(1)(J)

AMENDED LETTER OF TRANSMITTAL

Offer to Purchase for Cash

by

HUDSON TECHNOLOGIES, INC.

of

up to 1,167,400 Shares of its Common Stock

at a Purchase Price of $1.12 Per Share

THE TENDER OFFER, PRORATION PERIOD AND WITHDRAWAL RIGHTS WILL EXPIRE AT 5:00 P.M.,

NEW YORK CITY TIME, ON SEPTEMBER 7, 2007, UNLESS THE TENDER OFFER IS EXTENDED.

Hudson Technologies, Inc. (the “Company”) is offering to purchase up to 1,167,400 shares of its common stock, $.01 par value (“common stock”), in a tender offer, subject to the terms and conditions set forth in the Offer to Purchase dated June 29, 2007 (the “Offer to Purchase”). The offer is being made to all holders of the Company’s common stock at a price of $1.12 share. This Letter of Transmittal is to be completed only if: (a) certificates for shares are being forwarded herewith (and/or, in the case of pledged shares, you instruct the Company to forward certificates for such pledged shares) or (b) a tender of book entry shares is being made to the account maintained by Continental Stock Transfer & Trust Company, as Depositary (the “Depositary”), pursuant to Section 3 of the Offer to Purchase and related agent’s message is not being delivered.

ADDITIONAL INFORMATION AND ASSISTANCE

Questions and requests for assistance relating to the Tender Offer may be directed to the Depositary at 17 Battery Place, 8th Floor, New York, New York 10004 (telephone number: 212-509-4000, Ext. 536), or to the Company, at 275 North Middletown Road, Pearl River, New York 10965 (Attention: Stephen Mandracchia; telephone number: 845-735-6000, Ext. 604).
WHERE TO FORWARD YOUR TRANSMITTAL MATERIALS
By Mail: Continental Stock Transfer & Trust Company 17 Battery Place, 8th Floor New York, New York 10004	By Overnight Courier: Continental Stock Transfer & Trust Company 17 Battery Place, 8th Floor New York, New York 10004	By Hand: Continental Stock Transfer & Trust Company 17 Battery Place, 8th Floor New York, New York 10004
Delivery of this Letter of Transmittal to an address other than as set forth above will not constitute a valid delivery.
THE OFFER TO PURCHASE AND THIS LETTER OF TRANSMITTAL, INCLUDING THE ACCOMPANYING INSTRUCTIONS, SHOULD BE READ CAREFULLY BEFORE THIS LETTER OF TRANSMITTAL IS COMPLETED.

DESCRIPTION OF SHARES TENDERED
	Name(s) and Address(es) of Registered Owner(s) (Please Fill in, if Blank, Exactly as Name(s) Appear(s) on Share Certificate(s).				Shares Tendered (Attach additional signed list if necessary)
				1	Number of shares you own :
					Certificate Number(s):
					Book Entry:
				2	Number of shares you are tendering:
					Certificate Number(s):
					Book Entry:
				3	Conditional Tender - minimum number of shares that must be purchased:
					Certificate Number(s):
					Book Entry:
	Indicate below the order (by certificate number or date of pledge agreement) in which shares are to be purchased in the event of proration. If you do not designate an order, if less than all shares tendered are purchased due to proration, shares will be selected for purchase by the Depositary.
1st		2nd	3rd			4th	5th

Exhibit (a)(1)(J)

Note: Signatures must be provided below. Please read the accompanying instructions carefully

Ladies and Gentlemen:

The undersigned hereby tenders to the Company the above-described shares of common stock, at the price per share indicated in this Letter of Transmittal, net to the seller in cash, without interest, upon the terms and subject to the conditions set forth in the Offer to Purchase (receipt of which is hereby acknowledged) and in this Letter of Transmittal (which, together with the Offer to Purchase, as they may be amended and supplemented from time to time, constitute the “tender offer”).

Subject to, and effective upon, acceptance for payment of the shares tendered in accordance with the terms and subject to the conditions of the tender offer, including, if the tender offer is extended or amended, the terms and conditions of the extension or amendment, the undersigned agrees to sell, assign and transfer to, or upon the order of the Company, all right, title and interest in and to all shares tendered and orders the registration of all shares if tendered by book-entry transfer and irrevocably constitutes and appoints the Depositary as the true and lawful agent and attorney-in-fact of the undersigned with respect to the shares with full knowledge that the Depositary also acts as the agent of the Company, with full power of substitution (the power of attorney being deemed to be an irrevocable power coupled with an interest), to: (1) deliver certificates representing the shares or transfer ownership of the shares on the account books maintained by any book-entry transfer facility (as defined in the Offer to Purchase), together, in either case, with all accompanying evidences of transfer and authenticity, to or upon the order of the Company upon receipt by the Depositary, as the undersigned’s agent, of the purchase price with respect to the shares; (2) present certificates for the shares for cancellation and transfer on the Company’s books; and (3) receive all benefits and otherwise exercise all rights of beneficial ownership of the shares, subject to the next paragraph, all in accordance with the terms and subject to the conditions of the tender offer.

The undersigned covenants, represents and warrants to the Company that: (1) the undersigned has full power and authority to tender, sell, assign and transfer the shares tendered hereby and when and to the extent accepted for payment, the Company will acquire good, marketable and unencumbered title to the tendered shares, free and clear of all security interests, liens, restrictions, charges, encumbrances, conditional sales agreements or other obligations relating to the sale or transfer of the shares, and not subject to any adverse claims; (2) the undersigned understands that tenders of shares pursuant to any one of the procedures described in Section 3 of the Offer to Purchase and in the instructions will constitute the undersigned’s acceptance of the terms and conditions of the tender offer, including the undersigned’s representation and warranty that (i) the undersigned has a “net long position,” within the meaning of Rule 14e-4 promulgated under the Securities Exchange Act of 1934, in the shares or Equivalent Securities (as defined in the Offer to Purchase) at least equal to the shares being tendered, and (ii) the tender of shares complies with Rule 14e-4; (3) the undersigned will, upon request, execute and deliver any additional documents deemed by the Depositary or the Company to be necessary or desirable to complete the sale, assignment and transfer to the Company of the shares tendered; and (4) the undersigned has read, understands and agrees to all of the terms of the tender offer.

The undersigned understands that the Company’s acceptance of shares tendered pursuant to any one of the procedures described in Section 3 of the Offer to Purchase and in the instructions will constitute a binding agreement between the undersigned and the Company upon the terms and subject to the conditions of the tender offer. The undersigned acknowledges that under no circumstances will the Company pay interest on the purchase price, including without limitation, by reason of any delay in making payment.

All authority conferred or agreed to be conferred by this Letter of Transmittal will survive the death of incapacity of the undersigned, and any obligation of the undersigned will be binding on the heirs, personal representatives, executors, administrators, successors, assigns, trustees in bankruptcy and legal representatives of the undersigned. Except as stated in the Offer to Purchase, this tender is irrevocable.

The undersigned acknowledges that the undersigned has not relied on the Company in order to determine the tax consequences, in the undersigned’s particular circumstances, of tendering shares hereunder, including the application of federal, state, local and foreign tax laws, and has consulted with the undersigned’s own tax advisor if and as deemed by the undersigned to be appropriate to do so.

Please complete Box 8 if you would like checks made payable to a payee other than the record holder of shares tendered, and Box 9 if you would like checks or unaccepted shares mailed to an address other then the record address of the tendering shareholder. In all events, shares not accepted for payment will be issued in the name of the registered holder tendering such shares. Your ability to instruct us to make checks payable to a payee other than the registered holder is subject to your compliance with the requirements of this Letter of Transmittal, as determined by the Company.

4	Signature: This form must be signed by the registered holder(s) exactly as their name(s) appears above or by person(s) authorized to sign on behalf of the registered holder(s) by documents transmitted herewith.
X		||
Signature of Shareholder		Date	Daytime Telephone #
X		||
Signature of Shareholder		Date	Daytime Telephone #

5 SUBSTITUTE FORM W-9

PLEASE CERTIFY YOUR TAXPAYER ID OR SOCIAL SECURITY NUMBER BY SIGNING BELOW.

If the Taxpayer ID Number or Social Security Number printed above is INCORRECT OR if the space is BLANK write in the CORRECT number here. ®

Under penalties of perjury, I certify that:1. The number shown on this form is my correct taxpayer identification number (or I am waiting for a number to be issued to me), and2. I am not subject to backup withholding because: (a) I am exempt from backup withholding, or (b) I have not been notified by the Internal Revenue Service (IRS) that I am subject to backup withholding as a result of a failure to report all interest or dividends, or (c) the IRS has notified me that I am no longer subject to backup withholding, and3. I am a U.S. person (including a U.S. resident alien).

Certification instructions. You must cross out item 2 above if you have been notified by the IRS that you are currently subject to backup withholding because you have failed to report all interest or dividends on your tax return.

Signature:                                                                                     Date:

Exhibit (a)(1)(J)

6	ODD LOTS
As described in Section 1 of the Offer to Purchase, under certain conditions, holders holding 100 shares or less may have their shares accepted for payment before any proration of the purchase of other tendered shares. This preference is not available to partial tenders or to beneficial or record holders of an aggregate of more than 100 shares. Accordingly, this section is to be completed only if shares are being tendered by or on behalf of a person owning, beneficially or of record, 100 shares or less in the aggregate. The undersigned either (check one box):
r	is the beneficial or record owner of an aggregate of 100 shares or less, all of which are being tendered; or
r	is a broker, dealer, commercial bank, trust company, or other nominee that (a) is tendering for the beneficial owner(s), shares with respect to which it is the record holder, and (b) believes, based upon representations made to it by the beneficial owner(s), that each such person is the beneficial owner of an aggregate of 100 shares or less and is tendering all of the shares.

7		8
Special Payment Instructions		Special Delivery Instructions
If you want your check for cash to be issued in another name fill in this section with the information for the new account name.	Signature Guarantee	Fill in ONLY if mailing to someone other than the undersigned or to the undersigned at an address other than that shown on the front of this card. Mail certificate(s) and check(s) to:
Name (Please Print First, Middle & Last Name)	(Title of Officer Signing this Guarantee)	Name (Please Print First, Middle & Last Name)
Address           (Number and Street)	(Name of Guarantor Firm - Please Print)	Address           (Number and Street)
(City, State & Zip Code)	(Address of Guarantor Firm)
(Tax Identification or Social Security Number)	Authorized Signature	(City, State & Zip Code)

In the event you want your check for cash to be issued in another name (as authorized under Box 7 above), please check one of the boxes below, indicating that the payee is a nominee acting on your behalf (i.e., the payee has no economic interest in the proceeds of sale, the entirety of which interest remains in the record holder), or that the payee represents a party other than a nominee of the record holder. In the event the payee represents a party other than a nominee of the record holder, your ability to instruct us to deliver a check payable as set forth in Box 8 depends on your compliance with additional requirements established by the Company. Please contact the Company at the earliest opportunity to provide additional information regarding payees other than the record holder and its nominees.

r	The payee named in Box 7 is a nominee for the record holder
r	The payee named in Box 7 is not a nominee for the record holder.

Exhibit (a)(1)(J)

9     AFFIDAVIT OF LOST, MISSING OR DESTROYED CERTIFICATE(S) AND AGREEMENT OF INDEMNITY

If you cannot produce some or all of the Company’s stock certificates (other than in the case of pledged share evidenced by certificates held by the Company), you must obtain a lost instrument open penalty surety bond. Please refer to instruction 9 on the last page of this Form.

THIS AFFIDAVIT IS INVALID IF NOT SIGNED BELOW AND A CHECK IS NOT INCLUDED

TOTAL SHARES LOST    F		TOTAL SHARES LOSTF
Please Fill In Certificate No(s). if Known	Number of Shares	Please Fill In Certificate No(s). if Known	Number of Shares
Attach separate schedule if needed		Attach separate schedule if needed

By signing this form I/we swear, depose and state that: I/we am/are the lawful owner(s) of the certificate(s) hereinafter referred to as the “securities” described in the Letter of Transmittal. The securities have not been endorsed, pledged, cashed, negotiated, transferred, assigned, or otherwise disposed of. I/We have made a diligent search for the securities and have been unable to find it or them and make this Affidavit for the purpose of inducing the sale, exchange, redemption, or cancellation of the securities, as outlined in the Letter of Transmittal, without the surrender of the original(s), and also to request and induce Seaboard Surety Co. to provide suretyship for me to cover the missing securities under its Blanket Bond #764946. I/We hereby agree to surrender the securities for cancellation should I/we, at any time, find the securities.

I/We hereby agree for myself/ourselves, my/our heirs, successors, assigns and personal representatives, in consideration of the proceeds of the sale, exchange, redemption or cancellation of the securities, and the aforementioned suretyship, to indemnify, protect and hold harmless Seaboard Surety Co. (the Surety), Continental Stock Transfer & Trust Company, the Company, all their subsidiaries and any other party to the transaction, from and against any and all loss, costs, and damages including court costs and attorney’s fees, which they may be subject to or liable for in respect to the sale, exchange, redemption, or cancellation of the securities without requiring surrender of the original securities. The rights accruing to the parties under the preceding sentence shall not be limited or abridged by their negligence, inadvertence, accident, oversight, breach or failure to inquire into, contest, or litigate any claim, whenever such negligence, inadvertence, accident, oversight, breach or failure may occur or may have occurred, I/we agree that this Affidavit and Indemnity Agreement is to become part of Blanket Bond #764946 underwritten by Seaboard Surety Co..

Any person who, knowingly and with intent to defraud any insurance company or other person, files an application or statement of claim, containing any materially false information, or conceals for the purpose of misleading, information concerning any fact material thereto, commits a fraudulent insurance act, which is a crime, and shall also be subject to civil penalties as prescribed by law.

XSigned by Affiant (shareholder) _____________________________________________________ on this (date)

                                                                   (Deponent) (Indemnitor) (Heirs Individually)                                                  Month            Day           Year

Social Security #________________________________________ Date _____________________________ Notary Public

Lost Securities Surety Premium/Service Fee Calculation

The following formula should be used to calculate the surety premium, if any, and service fee that you must submit with this form.

1. Calculate the share value of the lost shares by multiplying the number of shares that are lost by the Cash Rate:

• Enter number of share(s) lost ____________________________________X $[_____] = $____________________________________share value

• If the share value exceeds $100,000, or if the shareholder is foreign or deceased, do not complete this affidavit. Complete only the Transmittal Form and contact Continental Stock Transfer & Trust Company regarding the lost certificate(s).

2. Calculate the Surety Premium..

• The surety premium equals 2% (.02) of the share value noted in line 1 above: $__________________ X (2%) or (.02) =....$_________________ Surety Premium

Please enclose a money order, certified check or cashiers’ check for the required amount, made payable to Continental Stock Transfer & Trust Company.

THIS AFFIDAVIT MUST BE NOTARIZED

Exhibit (a)(1)(J)

INSTRUCTIONS FOR COMPLETING THE LETTER OF TRANSMITTAL

1.	Your certificated share(s) and/or book entry shares you hold are shown in Box 1, together with applicable pledge agreements, if any.
2.	Please indicate the total number of certificated share(s) and/or book entry shares of the Company stock you are tendering in Box 2, if these shares are not subject to a pledge agreement.
3.	For Conditional Tenders pursuant to Section 6 of the Offer to Purchase, please indicate the minimum number of shares to be purchased.
4.	Sign, date and include your daytime telephone number in this Letter of Transmittal in Box 4 and, after completing all other applicable sections, return this form in the enclosed envelope. If your shares are represented by physical stock certificates (and are not pledged to the Company), include them in the enclosed envelope as well.
5.	PLEASE SIGN IN BOX 5 TO CERTIFY YOUR TAXPAYER ID OR SOCIAL SECURITY NUMBER if you are a U.S. Taxpayer. If the Taxpayer ID or Social Security Number is incorrect or blank, write the corrected number in Box 6 and sign to certify. Please note that Continental Stock Transfer & Trust Company may withhold 28% of your proceeds as required by the IRS if the Taxpayer ID or Social Security Number is not certified on our records. If you are a non-U.S. Taxpayer, please complete and return Form W-8BEN or other Form W-8. See the enclosed Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9 for additional instructions
6.	Please see the Offer to Purchase for additional information regarding Box 6.
7.	If you want your check for cash to be issued in another name, fill in Box 7 with the information for the new account name, and indicate whether the payee is your nominee. If you complete Box 7 your signature(s) must be guaranteed. If the payee named in Box 7 is not your nominee, you must contact the Company at the earliest opportunity to provide additional information regarding the payee.
8	Complete Box 8 only if the proceeds of this transaction and any unaccepted shares of the Company stock are to be delivered to an address that is not the record address of the registered holder (other than as authorized under Box 7).
9.	If you do not hold your shares in book-entry form and you cannot produce some or all of your Company stock certificates, you must obtain a lost instrument open penalty surety bond and file it with Continental Stock Transfer& Trust Company. To do so through Continental Stock Transfer & Trust Company’s program with Seaboard Surety Co., complete Box 9 above, including the lost securities premium, and return the form together with your payment as instructed. Please print clearly. Alternatively, you may obtain a lost instrument open penalty surety bond from an insurance company of your choice that is rated A+XV or better by A. M. Best & Company. In that instance, you would pay a surety premium directly to the surety bond provider you select and you would pay Continental Stock Transfer & Trust Company its service fee only. Please see the reverse side of this form on how to contact Continental Stock Transfer & Trust Company at the number provided for further instructions on obtaining your own bond.
10.	Shareholders who cannot deliver their certificates (or, in the case of pledged shares, authorize the Company to deliver their certificates) and all other required documents to the Depositary or complete the procedures for book-entry transfer prior to the expiration date (as defined in Section 1 of the Offer to Purchase) may tender their shares by properly completing and duly executing the Notice of Guaranteed Delivery pursuant to the guaranteed delivery procedures set forth in Section 3 of the Offer to Purchase.
11.	The Company will determine in its sole discretion the number of shares to accept, and the validity, eligibility and acceptance for payment of any tender. Any such determination will be final and binding on the parties. There is no obligation to give notice of any defects or irregularities to shareholders
12.	If any of the shares tendered hereby are owned of record by two or more joint owners, all such persons must sign this Letter of Transmittal. If any shares tendered hereby are registered in different names on several certificates, it will be necessary to complete, sign and submit as many separate Letters of Transmittal as there are different registrations of certificates. If this Letter of Transmittal or any certificate or stock power is signed by a trustee, executor, administrator, guardian, attorney-in-fact, officer of a corporation or other person acting in a fiduciary or representative capacity, he or she should so indicate when signing, and proper evidence satisfactory to the Company of his or her authority to so act must be submitted with this Letter of Transmittal. .
13.	If this Letter of Transmittal is signed by the registered owner(s) of the shares tendered hereby, no endorsements of certificates or separate stock powers are required unless payment of the purchase price is to be made to a person other than the registered owner(s). Signatures on any such certificates or stock powers must be guaranteed by an eligible institution. If this Letter of Transmittal is signed by a person other than the registered owner(s) of the shares tendered hereby, or if payment is to be made to a person other than the registered owner(s), the certificate(s) representing such shares must be properly endorsed for transfer or accompanied by appropriate stock powers, in either case signed exactly as the name(s) of the registered owner(s) appear(s) on the certificates(s). The signature(s) on any such certificate(s) or stock power(s) must be guaranteed by an eligible institution. In all cases, unaccepted shares will be issued in the name of the registered owner(s).
14.	If the space provided in Boxes 1, 2, 3, 7 or 8 above is inadequate, the certificate numbers and/or the number of shares should be listed on a separated signed schedule attached hereto.
15.	Partial Tenders (Not Applicable to Shareholders Who Tender by Book-Entry Transfer). If fewer than all the shares represented by any certificate submitted to the Depositary are to be tendered, fill in the number of shares that are to be tendered in Box 2. In that case, if any tendered shares are purchased, new certificate(s) for the remainder of the shares that were evidenced by the old certificate(s) will be sent to the registered holder(s), as soon as practicable after the acceptance for payment of, and payment for, the shares tendered herewith. All shares represented by certificates delivered to the Depositary will be deemed to have been tendered unless otherwise indicated.

EX-99.(A)(1)(K)

Exhibit (a)(1)(K)

Offer to Purchase for Cash

by

HUDSON TECHNOLOGIES, INC.

of

Up to 1,167,400 Shares of its Common Stock

at a Purchase Price of $1.12 Per Share

THE TENDER OFFER, PRORATION PERIOD, AND WITHDRAWAL RIGHTS WILL EXPIRE AT 5:00 PM, EASTERN TIME, ON SEPTEMBER 15, 2007 UNLESS THE TENDER OFFER IS FURTHER EXTENDED.

August 7, 2007

To Brokers, Dealers, Commercial Banks,

Trust Companies and Other Nominees:

Enclosed for your consideration is the Second Supplement to the Offer to Purchase, dated August 7, 2007, which further amends and supplements the Offer to Purchase, dated June 29, 2007 (the “Offer to Purchase”), relating to an offer by Hudson Technologies, Inc., a New York corporation (the “Company”), to purchase for cash up to 1,167,400 shares of its Common Stock, $0.01 par value per share (the “Common Stock”), at a price of $1.12 per share, net to the seller in cash, less any applicable withholding taxes and without interest, upon the terms and subject to the conditions described in the Offer to Purchase, as amended, and the Amended Letter of Transmittal (the “Amended Letter of Transmittal”) (which together, as they may be amended and supplemented from time to time, constitute the “Tender Offer”). Please furnish copies of the enclosed materials to those of your clients for whom you hold shares registered in your name or in the name of your nominee.

Enclosed with this letter are copies of the following documents:

1. Second Supplement to Offer to Purchase, dated August 7, 2007;

2. Amended Letter of Transmittal, for your use in accepting the Tender Offer and tendering shares of and for the information of your clients, including the Substitute Form W-9;

3. Amended Notice of Guaranteed Delivery with respect to shares, to be used to accept the Tender Offer in the event you are unable to deliver the share certificates, together with all other required documents, to the Depositary before the Expiration Time (as defined in the Offer to Purchase), or if the procedure for book-entry transfer cannot be completed before the Expiration Time;

4. Form of amended letter that may be sent to your clients for whose accounts you hold shares registered in your name or in the name of your nominee, along with an Instruction Form provided for obtaining such client’s instructions with regard to the Tender Offer; and

5. Return envelope addressed to Continental Stock Transfer & Trust Company as the Depositary.

Certain conditions to the Tender Offer are described in Section 7 of the Offer to Purchase.

We urge you to contact your clients promptly. Please note that the Tender Offer, proration period, and withdrawal rights will expire at 5:00 PM, Eastern Time, on September 7, 2007, unless the Tender Offer is further extended.

Under no circumstances will interest be paid on the purchase price of the shares regardless of any extension of, or amendment to, the Tender Offer or any delay in paying for such shares.

The Company will not pay any fees or commissions to any broker or dealer or other person (other than the Information Agent and Depositary, as described in the Offer to Purchase) in connection with the solicitation of tenders of shares pursuant to the Tender Offer. However, the Company will, on request, reimburse you for customary mailing and handling expenses incurred by you in forwarding copies of the enclosed Tender Offer materials to your clients. The Company will pay or cause to be paid any stock transfer taxes applicable to its purchase of shares pursuant to the Tender Offer, except as otherwise provided in the Offer to Purchase.

Questions may be directed to Continental Stock Transfer & Trust Company, the Depositary and Information Agent for the Tender Offer, at its address and telephone numbers listed on the back cover of the Offer to Purchase.

Very truly yours

Hudson Technologies Inc.

Nothing contained in this letter or in the enclosed documents shall render you or any other person the agent of the Company, the Depositary and Information Agent, or any affiliate of any of them or authorize you or any other person to give any information or use any document or make any statement on behalf of any of them with respect to the Tender Offer other than the enclosed documents and the statements contained therein.

EX-99.(A)(1)(L)

Exhibit (a)(1)(L)

Offer to Purchase for Cash

by

HUDSON TECHNOLOGIES, INC.

of

Up to 1,167,400 Shares of its Common Stock

at a Purchase Price of $1.12 Per Share

THE TENDER OFFER, PRORATION PERIOD, AND WITHDRAWAL RIGHTS WILL EXPIRE AT 5:00

PM, EASTERN TIME, ON SEPTEMBER 7, 2007, UNLESS THE TENDER OFFER IS EXTENDED.

To Our Clients:

Enclosed for your consideration is the Second Supplement to the Offer to Purchase, amending the offer to Purchase, dated June 29, 2007, and an Amended Letter of Transmittal (which, as may be amended or supplemented from time to time, together constitute the “Offer”) in connection with the Offer by Hudson Technologies, Inc., a New York corporation ( “Hudson”), to purchase for cash up to 1,167,400 shares of its common stock, $0.01 par value (such shares, together with all other outstanding shares of common stock of Hudson, are herein referred to as the “Shares”), at a price of $1.12 per Share, without interest, upon the terms and subject to the conditions of the Offer.

We are the holder of record of Shares held for your benefit and account. As such, we are the only ones who can tender your Shares pursuant to your instructions. The Letter of Transmittal is furnished to you for your information only and cannot be used by you to tender Shares held by us for your account.

Hudson will pay $1.12 per share for the Shares properly tendered but not withdrawn pursuant to the Offer and accepted for purchase taking into account the number of Shares so tendered. Hudson will purchase all Shares validly tendered and not withdrawn upon the terms and subject to the conditions set forth in the Offer to Purchase and the related Letter of Transmittal, including the provisions relating to “odd lot” tenders and conditional tenders described in the Offer to Purchase.

Shares tendered and not purchased because of proration or conditional tenders will be returned, at Hudson’s expense, to the stockholders who tendered such Shares promptly after the Expiration Date (as defined in the Offer to Purchase). Hudson also expressly reserves the right, in its sole discretion, to purchase additional Shares subject to applicable legal requirements. See Section 1 of the Offer to Purchase.

As described in the Offer to Purchase, if fewer than all Shares properly tendered but not withdrawn pursuant to the Offer are to be purchased by Hudson, Hudson will purchase tendered Shares in the following order of priority:

• First, Hudson will purchase all shares tendered by any stockholders who own beneficially or of record, an aggregate of 100 shares or less (“Odd Lots”) who :

• tenders all shares owned beneficially and of record by the Odd Lot Holder (tenders of less than all of the shares owned by an Odd Lot Holder will not qualify for this priority); and

• completes the section entitled “Odd Lots” in the Letter of Transmittal and, if applicable, in the Notice of Guaranteed Delivery.

• Second, subject to the conditional tender provisions described in Section 6 of the Offer to Purchase, Hudson will purchase up to 100% of the shares owned by all other shareholders from such other shareholders who properly tender up to 100% of all of their shares, on a pro rata basis with appropriate adjustments to avoid purchases of fractional shares, as described below.

As a result of the foregoing priorities applicable to the purchase of shares tendered, it is possible that all of the shares that a shareholder tenders in the Tender Offer may not be purchased. In addition, if a tender is conditioned upon the purchase of a specified number of shares, it is possible that none of those shares will be purchased

We request instructions as to whether you wish us to tender any or all of the Shares held by us for your account upon the terms and subject to the conditions set forth in the Offer to Purchase and the Letter of Transmittal.

1

Exhibit (a)(1)(L)

Please note carefully the following:

1. The Offer, the proration period and withdrawal rights expire at 5:00 PM, New York City time, on September 7, 2007 unless the Offer is extended by Hudson.

2. The Offer is not conditioned upon any minimum number of Shares being tendered. The Offer is, however, subject to certain other conditions set forth in the Offer to Purchase. See Section 7 of the Offer to Purchase.

3. The Offer is for 1,167,400 Shares, constituting approximately 4.4% of Hudson’s outstanding shares as of June 28, 2007.

4. Tendering stockholders who are registered stockholders or who tender their Shares directly to Continental Stock Transfer & Trust Company, the Depositary, will not be obligated to pay any brokerage commissions or fees to Hudson, solicitation fees, or, except as set forth in the Offer to Purchase and the Letter of Transmittal, stock transfer taxes on Hudson’s purchase of Shares pursuant to the Offer.

5. If you hold beneficially or of record an aggregate of 100 Shares or less, and you instruct us to tender on your behalf all such Shares before the Expiration Date (as defined in the Offer to Purchase) and check the box captioned “Odd Lots” on the attached Instruction Form, Hudson will accept all such Shares for purchase before proration, if any, of the purchase of other Shares properly tendered at or below the purchase price and not properly withdrawn pursuant to the Offer.

6. If you wish to condition your tender upon the purchase of a specified minimum number of the Shares , you may elect to do so and thereby avoid possible proration of your tender. To elect such a condition complete the section captioned “Conditional Tender” in the attached Instruction Form.

If you wish to have us tender any or all of your Shares, please so instruct us by completing, executing, detaching and returning to us the Instruction Form on the detachable part hereof. An envelope to return your instructions to us is enclosed. If you authorize tender of your Shares, all such Shares will be tendered unless otherwise specified on the Instruction Form.

YOUR PROMPT ACTION IS REQUESTED. YOUR INSTRUCTION FORM SHOULD BE FORWARDED TO US IN AMPLE TIME TO PERMIT US TO SUBMIT THE TENDER ON YOUR BEHALF BEFORE THE EXPIRATION OF THE OFFER.

The Offer is not being made to, nor will tenders be accepted from or on behalf of, holders of Shares in any jurisdiction in which the making of the Offer or acceptance thereof would violate the laws of such jurisdiction. In those jurisdictions the laws of which require that the Offer be made by a licensed broker or dealer, the Offer shall be deemed to be made on behalf of Hudson, or one or more registered brokers or dealers licensed under the laws of such jurisdiction.

2

Exhibit (a)(1)(L)

INSTRUCTION FORM

With Respect to the Offer by

HUDSON TECHNOLGIES, INC.

to Purchase for Cash Up to 1,167,400 Shares of its Common Stock

The undersigned acknowledge(s) receipt of your letter and the enclosed Second Supplement to the Offer to Purchase, which further amends and Supplements the Offer to Purchase, dated June 29, 2007 and the related Amended Letter of Transmittal (which together, as amended or supplemented, constitute the “Offer”), in connection with the offer by Hudson Technologies, Inc. , a New York corporation (“Hudson”), to purchase for cash up to 1,167,400 shares of its common stock, $0.01 par value (such shares, together with all other outstanding shares of common stock of Hudson, are herein referred to as the “Shares”), at a price of $1.12 per Share, without interest, upon the terms and subject to the conditions of the Offer.

The undersigned hereby instruct(s) you to tender to Hudson the number of Shares indicated below or, if no number is indicated, all Shares held by you for the account of the undersigned, upon the terms and subject to the conditions set forth in the Offer.

NUMBER OF SHARES BEING TENDERED HEREBY:  SHARES

* Unless otherwise indicated, it will be assumed that all Shares held by us for your account are to be tendered.

CHECK ONLY ONE BOX. IF MORE THAN ONE BOX IS CHECKED, OR IF NO BOX IS CHECKED, THERE IS NO VALID TENDER OF SHARES.

ODD LOTS

(See Instruction 6 of the Letter of Transmittal)

To be completed only if Shares are being tendered by or on behalf of a person owning, beneficially or of record, an aggregate of 100 Shares or less. This preference is not available to tenders of less than 100 shares or to beneficial or record holders of an aggregate of more than 100 Shares.

¨ By checking this box, the undersigned represents that it is the beneficial or record owner of an aggregate of 100 Shares or less, all of which are being tendered.

CONDITIONAL TENDER

(See Instruction 3 of the Letter of Transmittal)

A tendering shareholder may condition his or her tender of Shares upon Hudson purchasing a specified minimum number of the Shares tendered, all as described in Section 6 of the Offer to Purchase. Unless at least the minimum number of Shares you indicate below is purchased by Hudson pursuant to the terms of the Offer, none of the Shares tendered will be purchased. It is the tendering stockholder’s responsibility to calculate that minimum number of Shares that must be purchased if any are purchased, and each stockholder is urged to consult his or her own tax advisor. Unless this box has been checked and a minimum specified, your tender will be deemed unconditional.

¨ The minimum number of Shares that must be purchased, if any are purchased, is: _____ Shares.

If, because of proration, the minimum number of Shares designated will not be purchased, then none of the shares owned by the tendering shareholder will be tendered.

THE METHOD OF DELIVERY OF THIS DOCUMENT IS AT THE ELECTION AND RISK OF THE TENDERING STOCKHOLDER. IF DELIVERY IS BY MAIL, THEN REGISTERED MAIL WITH RETURN RECEIPT REQUESTED, PROPERLY INSURED, IS RECOMMENDED. IN ALL CASES, SUFFICIENT TIME SHOULD BE ALLOWED TO ENSURE TIMELY DELIVERY.

3

Exhibit (a)(1)(L)

SIGN HERE

Signature(s):

Name(s):

(PLEASE PRINT)

Taxpayer Identification or Social Security Number:

Address(es):

(INCLUDING ZIP CODE)

Area Code/Phone Number:

Date:

4

EX-99.(A)(1)(M)

Exhibit (a)(1)(M)

Second Supplement to Offer to Purchase dated June 29, 2007 for Cash up to 1,167,400 Shares of Common

Stock of Hudson Technologies, Inc. at a Purchase Price of

$1.12 Per Share

______________________________________

The Offer to Purchase, dated June 29, 2007, the related Letter of Transmittal (which together, as they may be amended and supplemented from time to time, constitute the “Tender Offer”) and related exhibits to the Schedule TO of Hudson Technologies, Inc. (“Company”), as amended and supplemented by Supplement dated July 2, 2007, relating to the Company’s offer to purchase up to 1,167,400 shares of its Common Stock, are hereby further amended to clarify that, for purposes of the Tender Offer and the related exhibits to the Company’s Schedule TO, including but not limited to the Letter of Transmittal;

a) Shareholders who own beneficially or of record more than 100 shares may tender up to 100% of these shares, subject to the odd lot and proration provisions in the Offer; and

b) The Tender Offer is hereby extended pursuant to Section 15 of the Offer to Purchase and will expire at 5:00 PM, Eastern Time, on September 7, 2007, unless further extended as described in Section 15.

August 7, 2007

EX-99.(A)(1)(N)

Exhibit (a)(1)(N)

AMENDED NOTICE OF GUARANTEED DELIVERY

for

Tender of Shares of Common Stock

of

HUDSON TECHNOLOGIES, INC.

        THE TENDER OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT MIDNIGHT, NEW YORK CITY TIME, ON SEPTEMBER 7, 2007, UNLESS THE TENDER OFFER IS EXTENDED.

        As set forth in Section 3 of the Offer to Purchase (as defined below), this form, or a form substantially equivalent to this form, must be used to accept the Offer (as defined below) if (1) certificates representing shares of common stock, $.01 par value per share, of Hudson Technologies, Inc., a New York corporation, are not immediately available, (2) the procedures for book-entry transfer cannot be completed on a timely basis or (3) time will not permit all required documents to reach the Depositary prior to the Expiration Date (as defined in the Offer to Purchase). This form may be delivered by hand or transmitted by facsimile transmission or mail to the Depositary. See Section 3 of the Offer to Purchase.

The Depositary for the Offer is:

CONTINENTAL STOCK TRANSFER & TRUST COMPANY

By Facsimile Transmission: (212) 616-7610

By Mail or Overnight Courier:	By Hand:
Continental Stock Transfer & Trust Company 17 Battery Place, 8th Floor New York, New York 10004	Continental Stock Transfer & Trust Company 17 Battery Place, 8th Floor New York, New York 10004

To Confirm Facsimile Transmissions: (212) 509-4000 ext. 536

DELIVERY OF THIS NOTICE OF GUARANTEED DELIVERY TO AN ADDRESS, OR TRANSMISSION OF INSTRUCTIONS VIA A FACSIMILE NUMBER, OTHER THAN AS SET FORTH ABOVE WILL NOT CONSTITUTE A VALID DELIVERY.

THIS NOTICE IS NOT TO BE USED TO GUARANTEE SIGNATURES. IF A SIGNATURE ON A LETTER OF TRANSMITTAL IS REQUIRED TO BE GUARANTEED BY AN ELIGIBLE INSTITUTION UNDER THE INSTRUCTIONS IN THE LETTER OF TRANSMITTAL, THE SIGNATURE GUARANTEE MUST APPEAR IN THE APPLICABLE SPACE PROVIDED IN THE SIGNATURE BOX ON THE LETTER OF TRANSMITTAL.

Exhibit (a)(1)(N)

Ladies and Gentlemen:

        The undersigned hereby tenders to Hudson Technologies, Inc., a New York corporation ("Hudson"), at the price per share indicated in this Notice of Guaranteed Delivery, on the terms and subject to the conditions set forth in the Offer to Purchase dated June 29, 2007 (the "Offer to Purchase"), and the related Letter of Transmittal (which, together with any amendments or supplements thereto, collectively constitute the "Offer"), receipt of which is hereby acknowledged, the number of shares set forth below, all pursuant to the guaranteed delivery procedures set forth in Section 3 of the Offer to Purchase. The shares of common stock of Hudson are referred to as "shares."

Number of Shares to be tendered: shares.

EX-99.(A)(1)(O)

Exhibit (a)(1)(O)

IMMEDIATE ATTENTION REQUIRED

August 7, 2007

Re: Hudson Technologies, Inc. Tender Offer

Dear Hudson Technologies, Inc. 401(K) Savings Plan Participant

NOTICE IS HEREBY GIVEN that, as previously advised by letter dated June 29, 2007, as of 5:00 PM, Eastern Time, on August 8, 2007, withdrawals, loans and distributions involving the Company common stock attributable to your Plan account will be unavailable for a period of time and, due to the extension of the tender offer as described in this notice, withdrawals, loans and distributions involving the Company common stock attributable to your Plan account will be unavailable for a period of time at least until September 20, 2007. Exchanges out of the Company’s common stock attributable to your Plan account will be unavailable and all outstanding orders to sell the Company’s common stock (e.g. good till cancelled limit) will be cancelled as of 5:00 PM, Eastern Time on September 4, 2007. The impact of this blackout is further described under the heading, “EFFECT OF THE OFFER ON YOUR ACCOUNT”.

The enclosed Second Supplement to the tender offer materials and Amended Direction Form require your immediate attention. Plan records reflect that, as a participant in the Hudson Technologies, Inc., 401(K) Savings Plan (the “Plan”), all or a portion of your individual account is invested in Hudson Technologies, Inc. (the “Company”) common stock. The tender offer materials previously provided describe an offer by the Company to purchase up to 1,167,400 shares of its common stock, $0.01 par value (the “Shares”), at a price of $1.12 per share, net to seller in cash, without interest (the “Offer”). As described below you have the right to instruct M&T Bank (“M&T”), as trustee of the Plan, concerning whether to tender Shares attributable to your individual account under the Plan. You will need to complete the enclosed Direction Form and return it to M&T in the enclosed return envelope so that it is RECEIVED by 5:00 PM., Eastern Time, on September 4, 2007, unless the offer is further extended, in which case the deadline for receipt of instructions will be three (3) business days prior to the expiration date of the Offer, if feasible.

The remainder of this letter summarizes the transaction, your rights under the Plan and the procedure for completing and submitting the Amended Direction Form. You should also review the more detailed explanation provided in the Offer to Purchase, dated June 29, 2007 (the “Offer to Purchase”), and the Supplement to the Offer to Purchase, dated July 2, 2007, that were previously provided to you, and you should also review the Second Supplement to the Offer to Purchase, dated August 7, 2007, which is enclosed with this letter.

BACKGROUND

The Company has made an Offer to its shareholders to tender up to 1,167,400 shares of its common stock, $0.01 par value, for purchase by the Company at a price of $1.12 per share, net to the seller in cash, without interest, upon the terms and subject to the conditions set forth in the Offer to Purchase, as supplemented.

The Offer to Purchase and supplements set forth the objectives, terms and conditions of the offer and are being provided to all of the Company’s shareholders. To understand the Offer fully and for a more complete description of the terms and conditions of the Offer, you should carefully read the entire Offer to Purchase, as supplemented.

The Offer extends to the Shares by the Plan. As of June 27, 2007, the Plan had approximately 59,529 Shares allocated to participant accounts. Only M&T, as trustee, can tender these Shares in the Offer. Nonetheless, as a participant under the Plan, you have the right to direct M&T whether or not to tender some or all of the Shares attributable to your individual account in the Plan. Unless otherwise required by applicable law, M&T will tender Shares attributable to participant accounts in accordance with participant instructions and M&T will not tender shares attributable to participant accounts for which it does not receive timely instructions. If you do not complete the enclosed Direction Form and return it to M&T on a timely basis, you will be deemed to have elected not to participate in the Offer and no Shares attributable to your account will be tendered.

1

Exhibit (a)(1)(O)

LIMITATIONS ON FOLLOWING DIRECTION

The enclosed Amended Direction Form allows you to specify up to 100 percent (100%) of the Shares attributable to your account to be tendered pursuant to the Offer to Purchase. As detailed below, when M&T tenders Shares on behalf of the Plan, it may be required to tender Shares on terms different than those set forth on your Direction Form.

The Employee Retirement Income Security Act of 1974, as amended (“ERISA”), and the trust agreement between the Company and M&T prohibit the sale of Shares to the Company for less than “adequate consideration” which is defined by ERISA for a publicly traded security as the price of the security prevailing on a national securities exchange. M&T will determine “adequate consideration”, based on the prevailing market price of the Shares on NASDAQ on or about the date the Shares are tendered to the Company by M&T (the “prevailing market price”). M&T will look to the NASDAQ Official Close Price as listed on Nasdaq.com. Accordingly, depending on the prevailing market price of the Shares on such date, M&T may be unable to follow participant directions to tender Shares to the Company. M&T will tender or not tender Shares as follows:

· If the prevailing market price is greater than the tender price offered by the Company ($1.12 per Share) notwithstanding your direction to tender Shares in the Offer, the Shares will not be tendered;

· If the prevailing market price is equal to or lower than the tender price offered, notwithstanding the lower closing market price, M&T will follow your direction as to the percentage, not to exceed 25 percent of Shares owned of Shares that you wish to tender.

Unless otherwise required by applicable law, M&T will not tender Shares for which it has received no direction, or for which it has received a direction not to tender. M&T makes no recommendation as to whether to direct the tender of Shares or whether to refrain from directing the tender of Shares. EACH PARTICIPANT OR BENEFICIARY MUST MAKE HIS OR HER OWN DECISIONS.

CONFIDENTIALITY

To assure the confidentiality of your decision, M&T and their affiliates or agents will tabulate the Direction Forms. Neither M&T nor their affiliates or agents will make your individual direction available to Hudson.

PROCEDURE FOR DIRECTING TRUSTEE

Enclosed is an Amended Direction Form that should be completed and returned to M&T. Please note that the Direction Form indicates the number of Shares attributable to your individual account as of June 28, 2007. However, for purposes of the final tabulation, M&T will apply your instructions to the number of Shares attributable to your account as of September 4, 2007, or as of a later date if the Offer is further extended.

If you do not properly complete the Amended Direction Form or do not return it by the deadline specified, such Shares will be considered NOT TENDERED.

To properly complete your Amended Direction form, you must do the following:

(1) On the face of the Amended Direction Form, check Box 1 or 2. CHECK ONLY ONE BOX:

· CHECK BOX 1 if you do not want any of the Shares attributable to your individual account tendered for sale in accordance with the terms of the Offer and simply want the Plan to continue holding such Shares.

· CHECK BOX 2 in all other cases and complete the table immediately below Box 2. Specify the percentage (in whole numbers) of Shares attributable to your individual account that you want to tender, up to a maximum of 100% of the shares attributable to your account.

(2) Date and sign the Amended Direction Form in the space provided.

2

Exhibit (a)(1)(O)

(3) Return the Amended Direction Form in the enclosed return envelope so that it is received by M&T at the address on the return envelope (Insert address) not later than 5:00 PM, Eastern Time, on September 4, 2007, unless the Offer is further extended, in which case the participant deadline shall be three (3) business days prior to the expiration date of the Offer, if feasible. If you wish to return the form by overnight courier, please send it to M&T at (Insert delivery address). Directions via facsimile or e-mail will not be accepted.

Your direction will be deemed irrevocable unless withdrawn by 5:00 PM on September 6, 2007, unless the Offer is further extended. In order to make and effective withdrawal, you must submit a new Amended Direction Form that may be obtained by calling M&T at 1-800-836-1431. Upon receipt of a new, completed and signed Amended Direction Form, your previous direction will be deemed canceled. You may direct the re-tendering of any Shares attributable to your individual account by obtaining an additional Amended Direction Form from M&T and repeating the previous instructions for directing tender as set forth in this letter.

After the deadline above for returning the Amended Direction Form to M&T and its affiliates or agents will complete the tabulation of all directions. M&T will tender the appropriate number of Shares on behalf of the Plan.

The Company will then buy all Shares, up to 1,167,400, that were properly tendered through the Offer. If there is an excess of Shares tendered over the exact number desired by the Company, Shares tendered pursuant to the Offer may be subject to proration, as described in the Offer to Purchase. For any Shares in the Plan that are tendered and purchased by the Company, the Company will pay cash to the Plan. INDIVIDUAL PARTICIPANTS IN THE PLAN WILL NOT, HOWEVER, RECEIVE ANY CASH TENDER PROCEEDS DIRECTLY. ALL SUCH PROCEEDS WILL REMAIN IN THE PLAN AND MAY BE WITHDRAWN ONLY IN ACCORDANCE WITH THE TERMS OF THE PLAN. Any Shares attributable to your account that are not purchased in the Offer will remain allocated to your individual account under the Plan.

The preferential treatment of holders of 100 Shares or less, will not apply to participants in the Plan, regardless of the number of Shares held within their individual accounts. Likewise, the conditional tender of Shares, as described in the Offer to Purchase, will not apply to the participants in the Plan.

EFFECT OF THE OFFER ON YOUR ACCOUNT

As previously advised by our letter, dated June 29, 2007, as of 5:00 PM, Eastern Time, on August 8, 2007, withdrawals, loans and distributions involving the Company common stock attributable to your Plan account will be unavailable for a period of time. Due to the Company’s extension of the Tender Offer, exchanges out of the Company’s common stock attributable to your Plan account will be unavailable and all outstanding orders to sell the Company’s common stock (e.g. good till cancelled limit) will be cancelled as of 5:00 PM, Eastern Time on September 4, 2007. Balances in the Company’s common stock will be utilized to calculate amounts eligible for loans and withdrawals throughout this restriction period. These restrictions will apply to ALL participants regardless if you elect to tender or not. While participants will not recognize any immediate tax gain or loss as a result of the tender offer, the tax treatment of future withdrawals or distributions from the Plan may be adversely impacted by a tender and sale of shares within the Plan. Specifically, under current federal income tax rules, if you receive from the Plan a lump sum distribution that includes the Company shares that have increased in value while they were held by the Plan, under certain circumstances, you may have the option of deferring paying taxes on this increase in value until you sell the shares. This is referred to as net unrealized appreciation. When the shares are sold, any gain up to the amount of the untaxed net unrealized appreciation is taxed as long-term capital gain. If shares credited to your individual Plan account are purchased by the Company in the tender offer, you will not longer be able to take advantage of this tax benefit on these shares. You should consult with your tax advisor concerning the tax aspects of this offer.

INVESTMENT OF PROCEEDS

M&T will invest proceeds received with respect to the Shares attributable to your account in the MTB Money Market fund as soon as administratively possible after receipt of proceeds. For all Shares tendered on your behalf that are accepted for purchase by the Company, M&T will process an exchange from the Tender Holding Fund, at a price equal to the purchase price in the Offer, into the MTB Money Market fund. For all Shares tendered on your behalf that are NOT accepted for purchase by the Company, such Shares will be transferred back into your common stock account. AT that time, for all of the Shares attributable to your account, you will have access to all transactions normally available to the Company common stock, subject to Plan rules.

3

Exhibit (a)(1)(O)

M&T anticipates that the processing of participant accounts will be completed five to seven business days after receipt of these proceeds. You may call EBS Benefit Solutions toll free at 1-888-887-4015, or access your account via the Participant Website @ www.ebs-benefits.com after the reinvestment is completed to learn the effect of the tender on your account or to have the proceeds from the sale of shares which were invested in the MTB Money Market fund invested in other investment options offered under the Plan.

SHARES OUTSIDE THE PLAN

If you hold Shares outside the Plan, you will receive under separate cover, Offer materials to be used to tender those Shares. Those Offer materials may not be used to direct M&T to tender or not tender the Shares attributable to your individual account under the Plan. Likewise, the tender of Shares attributable to your individual account under the Plan will not be effective with respect to Shares you hold outside of the Plan. The direction to tender or not tender Shares attributable to your individual account under the Plan may only be made in accordance with the procedures in this letter. Similarly, the enclosed Direction Form may not be used to tender Shares held outside of the Plan.

FURTHER INFORMATION

If you require additional information concerning the procedure to tender Shares attributable to your individual account under the Plan, please contact M&T toll free at 800-836-1431. If you require additional information concerning the terms and conditions of the Offer, please call Continental Stock Transfer & Trust Company, the information agent, toll free at 800-509-5586.

Sincerely

Hudson Technologies, Inc.

4

Exhibit (a)(1)(O)

AMENDED DIRECTION FORM

HUDSON TECHNOLOGIES, INC. TENDER OFFER

BEFORE COMPLETING THIS FORM, PLEASE READ CAREFULLY THE

ACCOMPANYING OFFER TO PURCHASE AND ALL OTHER ENCLOSED MATERIALS

PLEASE NOTE THAT IF YOU DO NOT SEND IN A PROPERLY COMPLETED, SIGNED DIRECTION FORM, OR IF SUCH DIRECTION FORM IS NOT RECEIVED BY 5:00 PM, EASTERN TIME, ON SEPTEMBER 4, 2007, UNLESS THE TENDER OFFER IS EXTENDED, THE COMPANY SHARES ATTRIBUTABLE TO YOUR ACCOUNT UNDER THE PLAN WILL NOT BE TENDERED IN ACCORDANCE WITH THE TENDER OFFFER, UNLESS OTHERWISE REQUIRED BY LAW.

M&T Bank (“M&T”) makes no representation to any participant in the Hudson Technologies, Inc. 401(K) Savings Plan (the “Plan”) as to whether to tender or not. Your direction to M&T will be kept confidential.

The Amended Direction Form, if properly signed, completed and received by M&T in a timely manner will supersede any previous Direction Form. I hereby acknowledge (i) receipt of the tender offer materials, including the Supplement to the Offer to Purchase dated July 2, 2007 and the letter dated June 29, 2007 enclosing those materials and this election form (ii) the Second Supplement to the Offer to Purchase, dated August 7, 2007 and (ii) that I have read and understand these materials and the limits or restrictions on my direction

As of June 28, 2007, the estimated number of shares attributable to your account in the Plan is shown to the right of your address on the label on the bottom of the page.

In connection with the Offer to Purchase made by Hudson Technologies, Inc., dated June 29, 2007, as amended, I hereby instruct M&T to tender the shares attributable to my account under the Plan as of September 4, 2007, unless a later deadline is announced, as follows (check only one box and complete):

(CHECK BOX ONE OR TWO)

¨ 1. Please refrain from tendering and continue to HOLD all shares attributable to my individual account under the Plan.

¨ 2. Please TENDER ______ % of the shares attributable to my individual account under the Plan. A blank space will be taken to mean that NO shares attributable to my account are to be tendered. (FILL IN THE BLANK ABOVE IF YOU HAVE CHECKED BOX 2).

Date

Please Print Name

Signature

5

EX-99.(A)(1)(P)

Exhibit (a)(1)(P)

HUDSON TECHNOLOGIES EXTENDS TENDER OFFER

TO SEPTEMBER 7, 2007

Pearl River, New York - August 7, 2007 - Hudson Technologies, Inc. (Nasdaq: HDSN) announced today that it has extended its Tender Offer to all of its common shareholders to purchase and retire up to approximately 1.2 million additional shares of its common stock at a purchase price of $1.12 per share. The Tender Offer will now expire at 5:00 PM Eastern Time on September 7, 2007.

Hudson also announced today that it has amended the Tender Offer to allow all shareholders to tender up to 100% of their shares to the Company, subject only to the “Odd Lot” priority and proration provisions of the Tender Offer.

About Hudson Technologies

Hudson Technologies, Inc. is a leading provider of innovative solutions to recurring problems within the refrigeration industry. Hudson’s proprietary RefrigerantSide® Services increase operating efficiency and energy savings, and remove moisture, oils and other contaminants frequently found in the refrigeration circuits of large comfort cooling and process refrigeration systems. Performed at a customer’s site as an integral part of an effective scheduled maintenance program or in response to emergencies, RefrigerantSide® Services offer significant savings to customers due to their ability to be completed rapidly and at higher purity levels, and can be utilized while the customer’s system continues to operate. In addition, the Company sells refrigerants and provides traditional reclamation services to the commercial and industrial air conditioning and refrigeration markets. For further information on Hudson, please visit the Company’s web site at www.hudsontech.com. Information on Hudson’s website is not a part of this release. 

This press release is for informational purposes only and is not an offer to buy or a solicitation of an offer to sell any shares of the Company’s common stock. The solicitation of offers to buy the Company’s common stockin the Tender Offerwill only be made pursuant to: i) the Offer to Purchase, and the related materials, and the Supplement to the Offer to Purchase, which have previously been filed with the SEC, and which were previously mailed to shareholders of record and made available for distribution to beneficial owners of the Company’s common stock; and ii) the Second Supplement to the Offer to Purchase, which will be filed with the SEC today, and which will be mailed to shareholders of record, and also will be made available for distribution to beneficial owners of the Company’s common stock. Shareholders should read all of those materials carefully because they will contain important information, including the various terms and conditions of the Tender Offer, as amended. Shareholders can obtain the Offer to Purchase, all related materials and all Supplements for free at the SEC website at www.sec.gov or from our information agent for the Tender Offer, Continental Stock Transfer and Trust Company, by calling (800) 509-5586.

Contact: Eric Anderson

Coltrin & Associates (for Hudson Technologies)

212-221-1616 ext.117 eric_anderson@coltrin.com