paribus

Paribus is a Latin term that appears as the ablative plural of pars. It is most famously seen in the phrase ceteris paribus, meaning “other things being equal.” In economics, philosophy, and the social sciences, the expression is used to indicate that all other relevant factors are held constant when analyzing the effect of a single variable.

Paribus is also the name of a former consumer technology company that operated in the online shopping space. The service was designed to help shoppers recover money when retailer prices dropped after a purchase by automatically filing price-adjustment requests under eligible retailers’ refund or price-matching policies.

The company gained attention for its automation of the price-tracking and refund-claim process, leveraging purchase data and receipts to submit requests on behalf of customers. In 2016, Paribus was acquired by Capital One, and the standalone service was subsequently integrated into Capital One’s product offerings. After the acquisition, Paribus as an independent brand ceased to operate as a separate service.

In current usage, the Latin phrase ceteris paribus remains common in discussions of theoretical models across economics and related disciplines, where it signals that comparisons are made while holding all other conditions constant. The Paribus brand, in contrast, is primarily of historical note as an example of a fintech service that aimed to automate consumer refunds through price adjustments.