Authorized Capital Stock—The Company was authorized to issue 25,000,000 shares of common stock, with a par value of $0.000004 per share as of June 30, 2020 and December 31, 2019.

Warrants—In May 2015, the Company issued warrants to acquire 116,350 shares of Common Stock at a price of approximately $17.19 per share to the placement agent as consideration for backstopping the financing completed in May 2015. There were no changes related to these warrants during the three and six months ended June 30, 2020 and June 30, 2019.

Common Stock Issuances and Repurchases—During the three and six months ended June 30, 2020, the Company issued 791,139 shares of common stock with an average price per share of $31.60, in connection with the CTEH business acquisition and issued 3,500 shares at an average price per share of $6.03, in connection with the exercise of certain employee stock options. During the three months ended June 30, 2019, the Company issued 125,031 shares of common stock with an average price per share of $26.90, in connection with the TES and TESUS business acquisition and 13,750 shares of common stock with an average price per share of $7.38, in connection with the exercise of certain employee stock options. During the six months ended June 30, 2019, the Company issued 125,031 shares of common stock with an average price per share of $26.90, in connection with the TES and TESUS business acquisition and 15,000 shares of common stock with an average price per share of $6.71, in connection with the exercise of certain employee stock options.

Employee Equity Incentive Plans—The Company has two plans under which stock-based awards have been issued: (i) the Montrose Amended& Restated 2017 Stock Incentive Plan (“2017 Plan”) and (ii) the Montrose Amended & Restated 2013 Stock Option Plan (“2013 Plan”) (collectively the “Plans”).

As of June 30, 2020 and June 30, 2019, there was $6.5 million and $6.8 million, respectively, of total unrecognized stock compensation expense related to unvested options and restricted stock granted under the Plans. Such unrecognized expense is expected to be recognized over the next two years. The following number of shares were authorized to be issued and available for grant as of June 30, 2020 and June 30, 2019:

	June 30, 2020
	2017 Plan		2013 Plan
Shares authorized to be issued		1,066,160		2,050,244
Shares available for grant		20,817		—

	June 30, 2019
	2017 Plan		2013 Plan
Shares authorized to be issued		981,800		2,074,604
Shares available for grant		201,183		—

	Three Months Ended June 30,
	2020								2019
	2017 plan				2013 plan				2017 plan				2013 plan
	Options		Restricted Stock		Options		Total		Options		Restricted Stock		Options		Total
Cost of revenue	$	342	$	—	$	61	$	403	$	205	$	—	$	147	$	352
Selling, general and administrative expense		299		370		68		737		145		110		687		942
	$	641	$	370	$	129	$	1,140	$	350	$	110	$	834	$	1,294

	Six Months Ended June 30,
	2020								2019
	2017 plan				2013 plan				2017 plan				2013 plan
	Options		Restricted Stock		Options		Total		Options		Restricted Stock		Options		Total
Cost of revenue	$	697	$	—	$	131	$	828	$	345	$	—	$	293	$	638
Selling, general and administrative expense		586		740		136		1,462		272		212		1,400		1,884
	$	1,283	$	740	$	267	$	2,290	$	617	$	212	$	1,693	$	2,522

Restricted Stock—During the six months ended June 30, 2020 and June 30, 2019, the Company issued 33,229 and 30,000 shares of restricted stock with a fair market value of $31.60 and $24.00 per share, respectively, to certain 2017 Plan participants as Director’s compensation. These shares of restricted stock granted in the six months ended June 30, 2020 vest one year from the date of grant and the shares of restricted stock granted during the six months ended June 30, 2019 vest over three years, or, in each case, in full upon a change in control, subject to the participant’s continued service as a Director throughout such date, or upon retirement. Members of the Board of Directors that receive stock-based compensation are treated as employees for accounting purposes. No restricted shares vested and were released as unrestricted shares of common stock during the six months ended June 30, 2020 and June 30, 2019. There were an aggregate of 273,122 and 242,025 restricted shares outstanding as of June 30, 2020 and June 30, 2019, respectively. There were no forfeitures, cancellations or expirations of restricted shares during the six and three months ended June 30, 2020 and June 30, 2019.

Options—Options issued to all optionees under the 2017 Plan vest over four years from the date of issuance (or earlier vesting start date, as determined by the Board of Directors) as follows: one half on the second anniversary of date of grant and the remaining half on the fourth anniversary of the date of grant, with the exception of certain annual grants to certain executive officers, which vest annually over a 3-year period. The following summarizes the options activity of the 2017 Plan for the six months ended June 30, 2020 and June 30, 2019:

	Options to Purchase Common Stock			Weighted- Average Exercise Price per Share		Weighted Average Grant Date Fair Value per Share		Weighted Average Remaining Contract Life (in Years)		Aggregate Intrinsic Value of In-The- Money Options (in Thousands)
Outstanding at December 31, 2018		257,762		$	20	$	10		—	$	1,151
Granted		308,990			24		13
Forfeitured/cancelled		(14,800	)		24
Outstanding at June 30, 2019		551,952			23		12		—		2,136

Outstanding at December 31, 2019		617,852			24		12		7.82		4,696
Granted		160,712			32		12
Forfeitured/cancelled		(5,500	)		20
Outstanding at June 30, 2020		773,064			26		12		8.03		4,651
Options vested and expected to vest		773,064		$	26				8.57	$	4,651

The following weighted-average assumptions were used in the Black-Sholes option-pricing model calculation for the six months ended June 30, 2020 and June 30, 2019:

Montrose Amended & Restated 2013 Stock Option Plan—The following summarizes the activity of the 2013 Plan for the six months ended June 30, 2020 and June 30, 2019:

	Options to Purchase Common Stock			Weighted- Average Exercise Price per Share		Weighted Average Grant Date Fair Value per Share		Weighted Average Remaining Contract Life (in Years)		Aggregate Intrinsic Value of In-The- Money Options (in Thousands)
Outstanding at December 31, 2018		1,900,404		$	6	$	1		7.30		33,290
Forfeitured/ cancelled		(12,600	)		14
Expired		(4,475	)		8
Exercised		(11,385	)		5						283
Outstanding at June 30, 2019		1,871,944			6		1		6.87		38,235

Outstanding at December 31, 2019		1,855,469			6		1		6.40		46,617
Forfeitured/ cancelled		(1,250	)		6
Expired		(8,550	)		6
Exercised		(3,500	)		6						89
Outstanding at June 30, 2020		1,842,169			6		1		5.91		46,276
Options vested and expected to vest		1,842,169			6				5.43		46,276

Total shares outstanding from exercised options were 205,100 shares and 201,600 shares as of June 30, 2020 and December 31, 2019.

Common Stock Reserved for Future Issuances—At June 30, 2020 and June 30, 2019, the Company has reserved certain stock of its authorized but unissued common stock for possible future issuance in connection with the following: