13D Filing: Engaged Capital and Aratana Therapeutics Inc. (PETX)

As of the close of
business on April 4, 2018, Messrs. Barbarosh, Ende and Robinson did not beneficially own any Shares, constituting 0% of the Shares
outstanding.

Each Reporting Person,
as a member of a “group” with the other Reporting Persons for the purposes of Section 13(d)(3) of the Securities Exchange
Act of 1934, as amended (the “Exchange Act”), may be deemed the beneficial owner of the Shares directly owned by the
other Reporting Persons.  The filing of this Schedule 13D shall not be deemed an admission that the Reporting Persons
are, for purposes of Section 13(d) of the Exchange Act, the beneficial owners of any securities of the Issuer he or it does not
directly own. Each of the Reporting Persons specifically disclaims beneficial ownership of the securities reported herein that
he or it does not directly own.

(b)       By
virtue of their respective positions with Engaged Capital Flagship Master, each of Engaged Capital Fund, Engaged Capital Offshore,
Engaged Capital, Engaged Holdings and Mr. Welling may be deemed to have sole power to vote and dispose of the Shares reported owned
by Engaged Capital Flagship Master.

By virtue of their
respective positions with the Engaged Capital Account, each of Engaged Capital, Engaged Holdings and Mr. Welling may be deemed
to have sole power to vote and dispose of the Shares held in the Engaged Capital Account.

(c)       Schedule
B annexed hereto lists all transactions in securities of the Issuer by the Reporting Persons during the past 60 days. All of such
transactions were effected in the open market.

(d)       No
person other than the Reporting Persons is known to have the right to receive, or the power to direct the receipt of dividends
from, or proceeds from the sale of, the Shares.

(e)       Not
applicable.

On April 4, 2017,
the Reporting Persons entered into a Joint Filing and Solicitation Agreement pursuant to which, among other things, the parties
agreed to (a) the joint filing on behalf of each of them of statements on Schedule 13D, and any amendments thereto, with respect
to the securities of the Issuer and (b) solicit proxies for the election of the Nominees at the Annual Meeting. A copy of the Joint
Filing and Solicitation Agreement is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

Engaged Capital Flagship
Master has entered into letter agreements pursuant to which it and its affiliates agreed to indemnify Messrs. Barbarosh, Ende and
Robinson against claims arising from the solicitation of proxies from the Issuer’s stockholders in connection with the Annual
Meeting and any related transactions. A form of the indemnification letter agreement is attached hereto as Exhibit 99.2 and is
incorporated herein by reference.