MERCK & CO. INC

$MRK

Last close: $111.90(2026-04-24)BRK current position: 9,157,192 shares ($0.71B as of 2021-06-30)Quarters with activity: 4CUSIP: 58933Y105

Price history with Berkshire transactions

InitiatedAddedTrimmedExited

MRK (indexed, 1× = first visible date)S&P 500 (indexed)Shares held (right axis)

Hover for daily price. Triangle markers show quarter-end Berkshire buy (▲ green) / sell (▼ orange/red) events from 13F-HR filings. Quarter-level granularity only — actual trade dates are not disclosed.

Berkshire's quarterly position history

Quarter	Shares	Δ Shares	Action	Value (USD)	13F
2021-06-30	9,157,192	-8,725,196	trimmed	$712.2M	View
2021-03-31	17,882,388	-10,815,047	trimmed	$1,378.6M	View
2020-12-31	28,697,435	+6,294,333	added	$2,347.5M	View
2020-09-30	22,403,102	+22,403,102	initiated	$1,858.3M	View

Prices via Yahoo Finance. Berkshire position data from quarterly 13F-HR filings. 13F has a ~45-day filing lag and only covers long US-listed equity positions. Cost basis below is approximated from the quarter-end value at which shares were added (FIFO).