The late John Mahoney left an estate worth “north of $5 million” according to documents obtained by celebrity news site TMZ.

This gave me a rare opportunity to fact-check various “celebrity net worth” sites.

• celebritynetworth.com says $16 million. Archived page. “All net worths are calculated by applying a proprietary algorithm. The results are then fact checked and confirmed by a team of editors. We scan all publicly available data and resources and work diligently to ensure that our numbers are the most accurate and up to date net worth data you will find anywhere on the internet.”
• networthpost.com says $15 million. Archived page. “According to authoritative sources, it has been estimated that John Mahoney’s net worth is as high as $15 million.” I like this hedge. It’s not saying that authoritative sources estimate Mahoney’s net worth at $15 million. It’s saying that authoritative sources have reported that Mahoney’s net worth has been estimated at $15 million.
• celebritynetworth123.com says $15 million. “The John Mahoney net worth and salary figures above have been reported from a number of credible sources and websites.” I suspect those credible sources and Web sites are “all the other celebrity net worth sites.”
• therichest.com says $15 million (archived page) and cites no sources.
• getnetworth.com says $15 million (archived page) and cites no sources.

My guess is that everybody copied their data from celebritynetworth.com, because their estimates all agree with the estimate of celebritynetworth.com as of 2017. celebritynetworth.com revised their estimate early in 2018, but the other sites haven’t caught up.

Now, technically, all of these estimates are “north of $5 million”, but one would think that if the documents said $15 million, TMZ would have reported something closer to that value. “North of $5 million” suggests that the actual value is between $5 million and $6 million.