3M CO — Director's Dealing 2010

May 3, 2010

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: 3M CO (MMM)
CIK: 0000066740
Period of Report: 2010-04-30

Reporting Person: Harlan Joe E (EXEC VP ELECTRO & COMMUN)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2010-04-30	Common Stock	M	17380	$64.50	Acquired	25087	Direct
2010-04-30	Common Stock	S	4480	$89.32	Disposed	20607	Direct
2010-04-30	Common Stock	S	8900	$89.321	Disposed	11707	Direct
2010-04-30	Common Stock	S	1000	$89.33	Disposed	10707	Direct
2010-04-30	Common Stock	S	100	$89.3304	Disposed	10607	Direct
2010-04-30	Common Stock	S	100	$89.3306	Disposed	10507	Direct
2010-04-30	Common Stock	S	2500	$89.331	Disposed	8007	Direct
2010-04-30	Common Stock	S	200	$89.35	Disposed	7807	Direct
2010-04-30	Common Stock	S	100	$89.3503	Disposed	7707	Direct
2010-04-30	Common Stock	M	17380	$61.85	Acquired	25087	Direct
2010-04-30	Common Stock	S	2371	$89.17	Disposed	22716	Direct
2010-04-30	Common Stock	S	5400	$89.171	Disposed	17316	Direct
2010-04-30	Common Stock	S	100	$89.1715	Disposed	17216	Direct
2010-04-30	Common Stock	S	300	$89.18	Disposed	16916	Direct
2010-04-30	Common Stock	S	1121	$89.19	Disposed	15795	Direct
2010-04-30	Common Stock	S	3500	$89.191	Disposed	12295	Direct
2010-04-30	Common Stock	S	100	$89.1928	Disposed	12195	Direct
2010-04-30	Common Stock	S	200	$89.20	Disposed	11995	Direct
2010-04-30	Common Stock	S	400	$89.21	Disposed	11595	Direct
2010-04-30	Common Stock	S	100	$89.2203	Disposed	11495	Direct
2010-04-30	Common Stock	S	2888	$89.25	Disposed	8607	Direct
2010-04-30	Common Stock	S	100	$89.2509	Disposed	8507	Direct
2010-04-30	Common Stock	S	100	$89.251	Disposed	8407	Direct
2010-04-30	Common Stock	S	100	$89.2605	Disposed	8307	Direct
2010-04-30	Common Stock	S	600	$89.27	Disposed	7707	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2010-04-30	Non-qualified Stock Option (Right to Buy)	$64.50	M	17380	Disposed	2012-05-14	Common Stock (17380)	Direct
2010-04-30	Non-qualified Stock Option (Right to Buy)	$61.85	M	17380	Disposed	2013-05-12	Common Stock (17380)	Direct

Footnotes

F1: Includes shares acquired under 3M's General Employee Stock Purchase Plan; includes shares acquired under 3M's Dividend Reinvestment Program.