UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 __________________________ FORM 10-Q (Mark One) þ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended April 30, 2019 or ¨ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 1-8929 ABM INDUSTRIES INCORPORATED (Exact name of registrant as specified in its charter) (State or othe ...