3M CO — Director's Dealing 2012

May 7, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: 3M CO (MMM)
CIK: 0000066740
Period of Report: 2012-05-03

Reporting Person: Woodworth John K (VICE PRESIDENT CORP SC OPERTNS)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-05-03	Common Stock	M	15018	$84.40	Acquired	29198	Direct
2012-05-03	Common Stock	F	14179	$89.39	Disposed	15019	Direct
2012-05-03	Common Stock	F	357	$89.39	Disposed	14662	Direct
2012-05-03	Common Stock	M	30532	$54.11	Acquired	45194	Direct
2012-05-03	Common Stock	S	43	$89.32	Disposed	45151	Direct
2012-05-03	Common Stock	S	1499	$89.33	Disposed	43652	Direct
2012-05-03	Common Stock	S	1052	$89.34	Disposed	42600	Direct
2012-05-03	Common Stock	S	5832	$89.35	Disposed	36768	Direct
2012-05-03	Common Stock	S	6516	$89.36	Disposed	30252	Direct
2012-05-03	Common Stock	S	1945	$89.37	Disposed	28307	Direct
2012-05-03	Common Stock	S	2626	$89.38	Disposed	25681	Direct
2012-05-03	Common Stock	S	2151	$89.39	Disposed	23530	Direct
2012-05-03	Common Stock	S	1792	$89.40	Disposed	21738	Direct
2012-05-03	Common Stock	S	1936	$89.41	Disposed	19802	Direct
2012-05-03	Common Stock	S	1957	$89.42	Disposed	17845	Direct
2012-05-03	Common Stock	S	1383	$89.43	Disposed	16462	Direct
2012-05-03	Common Stock	S	1600	$89.44	Disposed	14862	Direct
2012-05-03	Common Stock	S	100	$89.4415	Disposed	14762	Direct
2012-05-03	Common Stock	S	100	$89.445	Disposed	14662	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2012-05-03	Non-qualified Stock Option (Right to Buy)	$84.40	M	15018	Disposed	2014-05-09	Common Stock (15018)	Direct
2012-05-03	Non-qualified Stock Option (Right to Buy)	$54.11	M	30532	Disposed	2019-02-08	Common Stock (30532)	Direct
2012-05-03	Non-qualified Stock Option (Right to Buy)	$89.39	A	14536	Acquired	2014-05-09	Common Stock (14536)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	903.58	Indirect

Footnotes

F1: This Form is being filed to report the exercise of a 3M stock option for a total of 15,018 shares by means of a stock swap. A stock swap is a method of exercising a stock option in which the option holder attests to the ownership of enough shares of stock already owned by the option holder to cover the exercise price of the option being exercised. As a result of this stock swap, the reporting person acquired ownership of an additional 482 shares of 3M common stock. As a result of this transaction, 357 shares were sold to pay withholding taxes to the respective government agencies.

F2: Includes shares acquired pursuant to 3M's Dividend Reinvestment Plan.

F3: Includes dividend share equivalents, accrued quarterly, pursuant to 3M's Performance Awards Deferred Compensation Plan.