That said, interest in the religion is huge. Last week, HBO released a documentary on the Church of Scientology (COS), called Going Clear, which was watched by 1.7 million people (not counting those who streamed online), more than any HBO documentary in nearly a decade.

The documentary addresses Scientology’s tax-exempt status, which it won from the IRS in 1993. The film alleges that the COS was only declared tax-exempt by the IRS after it waged a decades-long campaign against the agency, which included filing dozens of lawsuits against both the organization and individual IRS workers, and hiring private investors and fake journalists to dig up incriminating information about individual IRS workers.

When the IRS finally granted the the church tax-exempt status, after an unconventional meeting between the then-commissioner Fred T. Goldberg and Scientology’s current leader David Miscavige, the financial ramifications were felt far and wide. Not only did the IRS stop demanding income taxes from the church, but local governments and states followed suit and granted the organization tax-exempt status.

The Church of Scientology vigorously disputes the film’s characterization of how it won its tax exempt status, writing in a letter to HBO, “Gibney’s film is replete with false and misleading statements and assertions about the relations between the IRS and the Church of Scientology and is nothing short of a vicious distortion of what actually occurred when the IRS recognized Scientology as a tax-exempt religious and charitable organization.” The Church did not respond to requests for comment for this article.

Regardless of how the church managed to win recognition as a tax-exempt religious organization, that prize is worth hard cash. According to Jeffrey Augustine, author of the blog The Scientology Money Project, the church has a book value of $1.75 billion, about $1.5 billion of which is tied up in real estate, mostly at its headquarters in Clearwater and in Hollywood, Calif. The Church also owns property in Seattle, London, and New York, among other places.

As for revenue, Augustine estimates that the church collects annual receipts of about $200 million, which he bases on conversations with former Scientology officials who have since left the organization. (Augustine is married to Karen de la Carriere, a former member of the church). He says about $125 million comes from the sale of auditing services to its followers, while the remainder comes from donations. How much of that revenue would actually be subject to income tax is difficult to say, however. Augustine estimates that much of the money that comes in is spent on legal defense of the church.

If the church were to have its tax-exempt status revoked, there would be no pressure by stakeholders to spend income efficiently. And even if the church were considered a for-profit organization by the feds, it’s easy to see it continuing to funnel its money into real estate purchases and deduct that money in the form of capital depreciation over the years. Whatever tax bills might be left over could be spent on salaries.

But let’s assume, for the sake of argument, that Scientology would have an operating profit margin of 10%, that would put its annual profits at $20 million. The average combined state and corporate income tax rate in the U.S is 39.1%, which would put their tax bill at about $7.82 million annually.

Much more significant than income taxes, however, are property taxes. Most states and localities exempt religious organizations from paying property taxes on buildings that are primarily used for purveying religious services. But many of The Church of Scientology’s buildings are used for other purposes, and so it ends up paying significant sums to local governments.

Augustine estimates that about 70% of the church’s property is tax exempt. The average commercial property tax rate in America is 1.940%, which would mean that the church is getting out of about another $20 million annually in property taxes, based on the estimate that it owns $1.5 billion in real estate.

The church may also manage to avoid other other taxes here and there. A Tampa Bay Times investigation from 2010 discusses how, for years, the church avoided paying a 5% occupancy tax for members who visit their facilities until Pinellas County Tax Collector pressed the issue five years ago. A Hollywood Reporter piece from 2011 details how the church gets hundreds of thousands of dollars in tax breaks from Los Angeles County for occupying and preserving historic buildings.

The biggest losers, then, from Scientology’s tax exempt status are likely the taxpayers of Clearwater and Los Angeles. But even in Clearwater, where the church is exempt from many taxes, it is the city’s largest taxpayer. In terms of revenue and overall value, Scientology is small potatoes—it probably couldn’t even be considered a mid-cap company. If Scientology isn’t a religion, then it’s just a very, very famous small business.

The church has managed to remain tax exempt because governments don’t have much to gain from fighting the idea. The people who really lose out, if you are to believe the testimonies of former members and numerous journalistic investigations, are those who fall sway to its philosophy. But these are folks who tend to be in search of some higher power, not those who have much power themselves.

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