Many tax liens and civil judgments soon will be taken off people’s credit reports, the latest move to omit negative information from the powerful financial scorecards.

The decision by the three major credit-reporting firms—Equifax Inc., Experian PLC and TransUnion—could help boost credit scores for millions of U.S. consumers, but could pose risks for lenders. The reports and scores often help decide how much consumers can borrow for a new house or car as well as determine their credit-card spending limit.

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