The Hyperfine 2021 Equity Incentive Plan (the “Hyperfine Plan”) is administered by the Company's board of directors. The board of directors may grant restricted stock units (“RSUs”) and options to purchase shares either as incentive stock options or non-qualified stock options, and other stock-based awards. The option grants are subject to certain terms and conditions, option periods and conditions, exercise rights and privileges as set forth in the Hyperfine Plan.

The following table summarizes the changes in the Company’s outstanding stock options for the three months ended March 31, 2022:


	Number of Options
Outstanding at January 1, 2022		7,522,136
Granted		4,231,693
Exercised		—
Forfeited		(271,368	)
Outstanding at March 31, 2022		11,482,461

In general, each award will vest based on continued service which is generally over 4 years. The grant date fair value of the award will be recognized as stock-based compensation expense over the requisite service period. The grant date fair value was determined using similar methods and assumptions as those previously disclosed by the Company.

The following table summarizes the changes in the Company’s outstanding restricted stock units for the three months ended March 31, 2022:


	Number of RSUs
Outstanding at January 1, 2022		117,516
Granted		1,660,535
Exercised		—
Forfeited		—
Outstanding at March 31, 2022		1,778,051

Included in the table above are service-based restricted stock units. During the three months ended March 31, 2022, the Company granted 1.7 million service-based awards. Each award will vest based on continued service which is generally over 3-4 years. The grant date fair value of the award will be recognized as stock-based compensation expense over the requisite service period. The fair value of restricted stock units was estimated on the date of grant based on the fair value of the Company’s Class A common stock.

On April 26, 2022, the Board of Directors approved a grant of 649,350 RSUs to the CEO having an aggregate value of $2,500 and which will be paid in four equal quarterly installments in February, May, August and November 2023.

The following table presents details of stock-based compensation expenses by functional line item noted within the Company's operating expenses:


	Three Months Ended March 31,
	2022		2021
Cost of sales - Device		16		—
Research and development		781		209
Sales and marketing		96		6
General and administrative		3,218		52
		4,111		267