May 15 (Reuters) - Two activist hedge funds, D.E. Shaw Group and Sachem Head Capital Management, have built small stakes in payroll-processing firm Automatic Data Processing Inc, the Wall Street Journal reported on Tuesday, citing people familiar with the matter.
The funds are not working together and have not decided whether they would try to push for changes at the company, according to the report here
The size of firms' stakes is unclear, WSJ said.
Billionaire investor William Ackman, who lost a proxy contest at ADP last year, said last month that he wants the company to succeed but said he might be back with a fight if ADP fails to perform.
D.E. Shaw, Sachem Head and ADP did not immediately respond to requests for comment.
Reporting by Munsif Vengattil and Parikshit Mishra in Bengaluru; Editing by Sriraj Kalluvila