UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): September 1, 2005

PHARSIGHT CORPORATION

(Exact name of registrant as specified in its charter)

Delaware	000-31253	77-0401273
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification Number)

800 W. El Camino Real

Mountain View, CA 94040

(Address and zip code of principal executive offices)

(650) 314-3800

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 3.02 Unregistered Sales of Equity Securities.

On September 1, 2005, we issued as a dividend 18,142 unregistered shares of our Series B redeemable convertible preferred stock to one of our Series A redeemable convertible preferred stockholders.

The holders of our Series A redeemable convertible preferred stock are entitled to receive an annual dividend at the rate of 8% of the original issue price of $4.008 on each outstanding share of Series A redeemable convertible preferred stock, which is payable quarterly in cash or shares of Series B redeemable convertible preferred stock at the election of the holder.

We believe this transaction was exempt from the registration requirements of the Securities Act of 1933, as amended, in reliance on Section 4(2) thereof or Regulation D promulgated thereunder, as a transaction by an issuer not involving a public offering.

Each share of Series B redeemable convertible preferred stock is convertible into four shares of our common stock at the election of the holder or upon the occurrence of certain other events described in our certificate of designations of Series A and Series B convertible preferred stock.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

PHARSIGHT CORPORATION
By:	/s/ Shawn M. O’Connor
	Shawn M. O’Connor
	President and Chief Executive Officer

Date: September 1, 2005

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