13G Filing: Clearline Capital and Apptio Inc

Exhibit 1

JOINT FILING AGREEMENT

This Joint Filing Agreement, dated as of April 5, 2017, is by and among
Clearline Capital LP, Clearline Capital LLC, Clearline Capital GP LLC and Marc
Majzner (collectively, the Filers).

Each of the Filers may be required to file with the United States Securities and
Exchange Commission a statement on Schedule 13D and/or 13G with respect to
shares of Class A Common Stock of Apptio Inc. beneficially owned by them from
time to time.

Pursuant to and in accordance with Rule 13(d)(1)(k) promulgated under the
Securities Exchange Act of 1934, as amended, the Filers hereby agree to file a
single statement on Schedule 13D and/or 13G (and any amendments thereto) on
behalf of each of the Filers, and hereby further agree to file this Joint Filing
Agreement as an exhibit to such statement, as required by such rule.

This Joint Filing Agreement may be terminated by any of the Filers upon written
notice or such lesser period of notice as the Filers may mutually agree.

Executed and delivered as of the date first above written.

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