During 2026, we sold all of our available-for-sale debt securities and used the proceeds to partially fund our acquisitions discussed in Note 6. Acquisitions, Collaborations and Other Arrangements. As such, there were no available-for-sale debt securities as of June 30, 2026.


	December 31, 2025
(in millions)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
U.S. treasury securities	$	1,222	$	3	$	—	$	1,224
U.S. government agencies securities	15		—		—		15
Corporate debt securities	1,392		7		—		1,398
Residential mortgage and asset-backed securities	405		2		—		407
Total	$	3,033	$	11	$	(1)	$	3,044

The total gross unrealized losses in the table above relate to available-for-sale debt securities, primarily corporate debt securities and U.S. treasury securities, with an estimated fair value of approximately $724 million that had been in a continuous unrealized loss position for less than 12 months as of December 31, 2025.

The following table summarizes the classification of our equity securities on our Condensed Consolidated Balance Sheets, including certain equity method investments for which we elected and applied the fair value option as we believe it best reflects the underlying economics of these investments:


(in millions)	June 30, 2026		December 31, 2025
Equity securities measured at fair value:
Cash and cash equivalents:
Money market funds	$	1,563	$	6,150
Prepaid and other current assets:
Equity method investment in Lakefront Biotherapeutics NV (“Lakefront”) (formerly known as Galapagos NV) – fair value option	500		551
Equity method investment in Arcus Biosciences, Inc. – fair value option	969		749
Other equity method investments – fair value option(1)	171		183
Other	63		499
Other long-term assets	431		386
Equity method investments and other equity securities without readily determinable fair values:
Other long-term assets(2)	295		393
Total	$	3,992	$	8,909

(2) Mostly comprised of equity interests in certain collaboration partners and investment funds that are considered to be variable interest entities (“VIEs”) for which we are not the primary beneficiary. Our maximum exposure to loss as a result of our involvement in these VIEs is limited to the value of our investment.

The following table summarizes net unrealized gains and losses related to equity securities still held as of the respective ending balance sheet dates for the periods below, included in Other (income) expense, net on our Condensed Consolidated Statements of Operations:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
(in millions)	2026		2025		2026		2025
Unrealized (gain) loss, net, related to fair value option investments	$	(289)	$	(72)	$	(143)	$	204
Unrealized (gain) loss, net, related to all other equity investments	(51)		(71)		6		89
Total unrealized (gain) loss, net	$	(340)	$	(143)	$	(137)	$	293

During the six months ended June 30, 2026, we donated certain equity securities to the Gilead Foundation, a California nonprofit public benefit corporation for which certain of our officers serve as directors, and recorded a related expense of $63 million in Selling, general and administrative expenses on our Condensed Consolidated Statements of Operations.