IBM Corp. did not commit age discrimination when it changed its pension coverage in the 1990s, a federal appeals court ruled Monday in an influential case that Big Blue had agreed to settle for up to $1.4 billion if it had lost the appeal.

The case involved 140,000 older employees who were affected when IBM converted to a “cash-balance” plan, which gives workers virtual accounts that can be cashed out for a lump sum when they leave the company.