REVENUES

12 Months Ended

Dec. 31, 2022

REVENUES

REVENUES

3. REVENUES

Revenues disaggregated by category were as follows (in thousands):

	Year Ended December 31,
	2022		2021		2020
Product sales:
Gross product sales	$	108,523	$	81,186	$	76,470
Discounts and allowances		(31,805)		(18,176)		(14,774)
Total product sales, net		76,718		63,010		61,696
Revenues from collaborations:
License revenues		7,932		70,553		40,358
Development milestones		25,000		1,875		2,100
Research and development services and others		6,092		3,298		4,467
Total revenues from collaborations		39,024		75,726		46,925
Government contract		4,500		10,500		—
Total revenues	$	120,242	$	149,236	$	108,621

Revenue from product sales is primarily related to sales of our first commercial product, TAVALISSE. In December 2022, following the FDA approval of our second commercial product, REZLIDHIA, we delivered product quantities to our customers and recognized $0.9 million of net revenue included within net product sales for the year ended December 31, 2022. Our net product sales include sale of products to our specialty distributors, net of chargebacks, discounts and fees, government and other rebates and returns. The following tables summarize the activities in chargebacks, discounts and fees, government and other rebates and returns that were accounted for within other accrued liabilities, for each of the periods presented (in thousands):

	Chargebacks,		Government
	Discounts and		and Other
	Fees		Rebates		Returns		Total
Balance as of January 1, 2022	$	3,404	$	2,494	$	2,017	$	7,915
Provision related to current period sales		23,488		5,901		1,514		30,903
Credit or payments made during the period		(20,679)		(5,759)		(235)		(26,673)
Balance as of December 31, 2022	$	6,213	$	2,636	$	3,296	$	12,145

	Chargebacks,		Government
	Discounts and		and Other
	Fees		Rebates		Returns		Total
Balance as of January 1, 2021	$	2,461	$	2,115	$	1,489	$	6,065
Provision related to current period sales		10,731		5,036		1,021		16,788
Credit or payments made during the period		(9,788)		(4,657)		(493)		(14,938)
Balance as of December 31, 2021	$	3,404	$	2,494	$	2,017	$	7,915

Of the $31.8 million discounts and allowances from gross product sales for the year ended December 31, 2022, $30.9 million was accounted for as additions to revenue reserves and refund liability and $0.9 million as reductions in accounts receivable (as it relates to allowance for prompt pay discount) and prepaid and other current assets (as it relates to certain chargebacks and other fees that were prepaid) in the balance sheet.

Of the $18.2 million discounts and allowances from gross product sales for the year ended December 31, 2021, $16.8 million was accounted for as additions to revenue reserves and refund liability and $1.4 million as reductions in accounts receivable (as it relates to allowance for prompt pay discount) and prepaid and other current assets (as it relates to certain chargebacks and other fees that were prepaid) in the balance sheet.

For detailed discussions of our revenues from collaboration and government contract, see “Note 4 – Sponsored Research and License Agreements and Government Contract” below.

The following table summarizes revenues from each of our customers who individually accounted for 10% or more (wherein * denotes less than 10%) of the total net product sales and revenues from collaborations:

	Year Ended December 31,
	2022		2021		2020
McKesson Specialty Care Distribution Corporation		31%		20%		23%
Kissei		24%		*		—
Cardinal Healthcare		19%		*		*
ASD Healthcare and Oncology Supply		17%		17%		30%
Lilly		*		48%		—
Grifols		*		*		41%