Equity

12 Months Ended

Dec. 31, 2022

Equity [Abstract]

Equity

Equity

The Merck certificate of incorporation authorizes 6,500,000,000 shares of common stock and 20,000,000 shares of preferred stock.

Capital Stock

A summary of common stock and treasury stock transactions (shares in millions) is as follows:

	2022		2021		2020
	Common Stock	Treasury Stock	Common Stock	Treasury Stock	Common Stock	Treasury Stock
Balance January 1	3,577	1,049	3,577	1,047	3,577	1,038
Purchases of treasury stock	—	—	—	11	—	16
Issuances (1)	—	(10)	—	(9)	—	(7)
Balance December 31	3,577	1,039	3,577	1,049	3,577	1,047

(1)     Issuances primarily reflect activity under share-based compensation plans.