WASHINGTON, Sept. 7 (Bloomberg News) — The House approved the most sweeping changes to United States patent law in more than half a century on Friday in a victory for computer companies like Microsoft and finance companies like Goldman Sachs.

The legislation, approved 220 to 175, would make patents harder to obtain and easier to challenge and is intended to curtail litigation by limiting where patent owners can file suit and how much they can collect in damages.

Approval came after last-minute changes to appease critics, including labor groups, universities, the Bush administration and the drug maker Pfizer, which said the original proposal went too far in weakening patent rights and might hurt investment in new technologies and cost American jobs.

Even with the changes, the measure faced opposition from manufacturers, including Caterpillar, Eli Lilly and Procter & Gamble. Opponents said the measure favored certain industries over others.