SAN DIEGO (AP) — Lottery bids for highly educated worker visas plunged nearly 40% this year, authorities said Tuesday, claiming success against people who were “gaming the system” by submitting multiple, sometimes dubious, applications to unfairly increase chances of being selected.

Major technology companies that use H-1B visas sought changes after massive increases in bids left their employees and prospective hires with slimmer chances of winning the random lottery. Facing what it acknowledged was likely fraud and abuse, U.S. Citizenship and Immigration Services this year said each employee had only one shot at the lottery, whether the person had one job offer or 50.

The government received 470,342 entries for this year’s lottery, which was held the last week of March, down 38% from 758,994 entries last year. The number of workers who applied was little changed — about 442,000 this year compared with 446,000 last year — indicating a sharp drop in people who applied multiple times.