

	Three Months Ended September 30,
	Common Stock			Other Paid-In Capital		Retained Earnings			Accumulated Other Comprehensive Loss			Treasury Stock					Non- Controlling Interests			Total
($ and shares in millions)	Shares	Par Value		Other Paid-In Capital		Retained Earnings			Accumulated Other Comprehensive Loss			Shares		Cost			Non- Controlling Interests			Total
Balance at July 1, 2017	3,577	$	1,788	$	39,776	$	45,046		$	(5,094	)	850		$	(42,053	)	$	249		$	39,712
Net loss attributable to Merck & Co., Inc.	—	—		—		(56		)	—			—		—			—			(56		)
Other comprehensive income, net of taxes	—	—		—		—			149			—		—			—			149
Cash dividends declared on common stock ($0.47 per share)	—	—		—		(1,289		)	—			—		—			—			(1,289		)
Treasury stock shares purchased	—	—		—		—			—			2		(159		)	—			(159		)
Share-based compensation plans and other	—	—		47		—			—			(1	)	93			—			140
Net income attributable to noncontrolling interests	—	—		—		—			—			—		—			5			5
Distributions attributable to noncontrolling interests	—	—		—		—			—			—		—			(3		)	(3		)
Balance at September 30, 2017	3,577	$	1,788	$	39,823	$	43,701		$	(4,945	)	851		$	(42,119	)	$	251		$	38,499
Balance at July 1, 2018	3,577	$	1,788	$	39,741	$	41,523		$	(5,122	)	907		$	(45,401	)	$	237		$	32,766
Net income attributable to Merck & Co., Inc.	—	—		—		1,950			—			—		—			—			1,950
Other comprehensive loss, net of taxes	—	—		—		—			(29		)	—		—			—			(29		)
Cash dividends declared on common stock ($0.48 per share)	—	—		—		(1,284		)	—			—		—			—			(1,284		)
Treasury stock shares purchased	—	—		—		—			—			16		(996		)	—			(996		)
Share-based compensation plans and other	—	—		21		—			—			(5	)	231			—			252
Net income attributable to noncontrolling interests	—	—		—		—			—			—		—			8			8
Distributions attributable to noncontrolling interests	—	—		—		—			—			—		—			(11		)	(11		)
Balance at September 30, 2018	3,577	$	1,788	$	39,762	$	42,189		$	(5,151	)	918		$	(46,166	)	$	234		$	32,656



	Nine Months Ended September 30,
	Common Stock			Other Paid-In Capital			Retained Earnings			Accumulated Other Comprehensive Loss			Treasury Stock					Non- Controlling Interests			Total
($ and shares in millions)	Shares	Par Value		Other Paid-In Capital			Retained Earnings			Accumulated Other Comprehensive Loss			Shares		Cost			Non- Controlling Interests			Total
Balance at January 1, 2017	3,577	$	1,788	$	39,939		$	44,133		$	(5,226	)	828		$	(40,546	)	$	220		$	40,308
Net income attributable to Merck & Co., Inc.	—	—		—			3,440			—			—		—			—			3,440
Other comprehensive income, net of taxes	—	—		—			—			281			—		—			—			281
Cash dividends declared on common stock ($1.41 per share)	—	—		—			(3,872		)	—			—		—			—			(3,872		)
Treasury stock shares purchased	—	—		—			—			—			36		(2,312		)	—			(2,312		)
Share-based compensation plans and other	—	—		(116		)	—			—			(13	)	739			—			623
Acquisition of Vallée	—	—		—			—			—			—		—			25			25
Net income attributable to noncontrolling interests	—	—		—			—			—			—		—			16			16
Distributions attributable to noncontrolling interests	—	—		—			—			—			—		—			(10		)	(10		)
Balance at September 30, 2017	3,577	$	1,788	$	39,823		$	43,701		$	(4,945	)	851		$	(42,119	)	$	251		$	38,499
Balance at January 1, 2018	3,577	$	1,788	$	39,902		$	41,350		$	(4,910	)	880		$	(43,794	)	$	233		$	34,569
Adoption of new accounting standards (see Note 1)	—	—		—			322			(274		)	—		—			—			48
Net income attributable to Merck & Co., Inc.	—	—		—			4,393			—			—		—			—			4,393
Other comprehensive income, net of taxes	—	—		—			—			33			—		—			—			33
Cash dividends declared on common stock ($1.44 per share)	—	—		—			(3,876		)	—			—		—			—			(3,876		)
Treasury stock shares purchased	—	—		—			—			—			53		(3,158		)	—			(3,158		)
Share-based compensation plans and other	—	—		(140		)	—			—			(15	)	786			—			646
Net income attributable to noncontrolling interests	—	—		—			—			—			—		—			22			22
Distributions attributable to noncontrolling interests	—	—		—			—			—			—		—			(21		)	(21		)
Balance at September 30, 2018	3,577	$	1,788	$	39,762		$	42,189		$	(5,151	)	918		$	(46,166	)	$	234		$	32,656