AGREEMENT TO VOTE SHARES

Exhibit 2.2

AGREEMENT TO VOTE SHARES

        This Agreement to Vote Shares relates to that certain Agreement and Plan of Merger dated as of May 11, 2005, among Firstbank Corporation, a Michigan corporation; Keystone Financial Corporation, a Michigan corporation; and Keystone Community Bank, a Michigan banking corporation (the “Agreement”). Capitalized terms used but not defined herein shall have the meanings assigned to them in the Agreement.

        The undersigned directors of Keystone hereby covenant and agree to vote the shares of Keystone Common Stock owned by them (including all shares of Keystone Common Stock over which such directors exercise direct or indirect voting control, including, but not limited to, a trust of which the shareholder is the grantor and trustee, a trust whose sole present beneficiaries are the shareholder’s family members or an individual retirement account (XXX) in the name of the shareholder), in favor of the Agreement at the Keystone Shareholders Meeting called to approve the Agreement.

Director Name and Address

X. Xxxx Xxxxx III
000 Xxxx Xxxxxxxx Xxxxxx
Xxxxxxxxx, Xxxxxxxx 00000



Xxxxxx X. Xxxxxxxxx
000 Xxxx Xxxxxxxx Xxxxxx
Xxxxxxxxx, Xxxxxxxx 00000



Xxxxxx X. Field
000 Xxxx Xxxxxxxx Xxxxxx
Xxxxxxxxx, Xxxxxxxx 00000



Xxxx X. Xxxxxxx
0000 Xxxxxxx Xxxx
Xxxxxxxxx, Xxxxxxxx 00000



Xxxx X. Xxxxxxx
000 X. Xxxx Xxxxxx, Xxxxx 000
Xxxxxxxxx, Xxxxxxxx 00000 # Shares of Keystone Owned

No. of Shares: 13,020

/s/ X. Xxxx Xxxxx
————————————————————
                           Signature

No. of Shares: 5,668.75

/s/ Xxxxxx X. Xxxxxxxxx
————————————————————
                           Signature

No. of Shares: 33,750

/s/ Xxxxxx X. Field
————————————————————
                           Signature

No. of Shares: 39,375

/s/ Xxxx Xxxxxxx
————————————————————
                           Signature

No. of Shares: 17,293.75

/s/ Xxxx X. Xxxxxxx
————————————————————
                           Signature

(continued on next page)

Xxxxxxx X. Xxxxxx
0000 Xxxxxxxxx Xxxx.
Xxxxxxxxx, Xxxxxxxx 00000




Xxxx X. Xxxxxxxxxx, M.D.
0000 X. Xxxx Xxxxxx
Xxxxxxxxx, Xxxxxxxx 00000




Xxxxxx X. Xxxxxxx
0000 Xxxx
Xxxxxxxxx, Xxxxxxxx 00000 No. of Shares: 22,500

/s/ Xxxxxxx X. Xxxxxx
————————————————————
                           Signature


No. of Shares: 33,750

/s/ Xxxx X. Xxxxxxxxxx
————————————————————
                           Signature


No. of Shares: 0

Xxxxxx X. Xxxxxxx
————————————————————
                           Signature