Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	Owned after	D/I
Restricted Stock Units^F3,F6,F7	—	May 12, 2016	M	3,162	D	—	—	Common Stock	3,162	0	D
Dividend Equivalent Rights^F3,F8,F9	—	May 12, 2016	M	66	D	—	—	Common Stock	66	0	D
Restricted Stock Units^{F10,F12,F3,F6,F11}	—	May 13, 2016	A	3,628	A	—	—	Common Stock	3,628	3,628	D

Explanation of responses

F1Settlement of restricted stock units ("RSUs") and related dividend equivalents.
F10The RSUs represent the reporting person's annual equity award under the Allison Transmission Holdings, Inc. (the "Company") Second Amended and Restated Non-Employee Director Compensation Policy ("Policy").
F11The RSUs vest on the date of the next annual meeting of the stockholders of the Company. Unvested RSUs earn dividend equivalents when dividends are declared on the Company's common stock.
F12The number of RSUs received was calculated based on $27.56, which was the closing price of the Company's Common Stock on the date of grant.
F2Includes 66 dividend equivalents.
F3Under an agreement with ValueAct Capital, Gregory P. Spivy is deemed to hold the common stock for the benefit of ValueAct Capital Master Fund, L.P. and indirectly for (i) VA Partners I, LLC as General Partner of ValueAct Capital Master Fund, L.P., (ii) ValueAct Capital Management, L.P. as the manager of ValueAct Capital Master Fund, L.P., (iii) ValueAct Capital Management, LLC as General Partner of ValueAct Capital Management, L.P., (iv) ValueAct Holdings, L.P. as the sole owner of the limited partnership interests of ValueAct Capital Management, L.P. and the membership interests of ValueAct Capital Management, LLC and as the majority owner of the membership interests of VA Partners I, LLC and (v) ValueAct Holdings GP, LLC as General Partner of ValueAct Holdings, L.P.
F4Each reporting person listed herein disclaims beneficial ownership of the reported securities except to the extent of its pecuniary interest therein, and this report shall not be deemed an admission that such person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.
F5The securities reported herein are directly beneficially owned by ValueAct Capital Master Fund, L.P. and may be deemed to be indirectly beneficially owned by (i) VA Partners I, LLC as General Partner of ValueAct Capital Master Fund, L.P. , (ii) ValueAct Capital Management, L.P. as the manager of ValueAct Capital Master Fund, L.P. , (iii) ValueAct Capital Management, LLC as General Partner of ValueAct Capital Management, L.P., (iv) ValueAct Holdings, L.P. as the sole owner of the limited partnership interests of ValueAct Capital Management, L.P. and the membership interests of ValueAct Capital Management, LLC and as the majority owner of the membership interests of VA Partners I, LLC and (v) ValueAct Holdings GP, LLC as General Partner of ValueAct Holdings, L.P.
F6Each RSU represents a contingent right to receive one share of the Company's common stock.
F7On May 14, 2015, the reporting person was granted 3,162 RSUs that vested on May 12, 2016.
F8Each dividend equivalent right represents a contingent right to receive one share of the Company's common stock.
F9The dividend equivalent rights accrued on previously awarded RSUs and vested on May 12, 2016.

Remarks

Explanation of Responses: - The reporting persons herein may be deemed to be members of a "group" for purposes of the Securities Exchange Act of 1934, as amended. Each reporting person disclaims beneficial ownership of any securities deemed to be owned by the group that are not directly owned by such reporting person. This report shall not be deemed an admission that such reporting person is a member of a group or the beneficial owner of any securities not directly owned by such reporting person. - Gregory P. Spivy, a Partner at ValueAct Capital, serves on the board of directors of the Issuer. As a result, the other reporting persons herein may be deemed directors by deputization.