Do you use a comma with LLC's?

My Handbook of Commercial Correspondence (an OUP publication) invariably avoids commas.

NZ Business Machines Pty.
Glaston Potteries Ltd.
P. Marlow & Co. Ltd.
Omega S.p.A.
Hartley-Mason Inc.
SP Wholesalers PLC
R.G. Electronics AG

1b00LLC.02b00 Limited liability company. Never use a comma before "LLC," even if the company prefers it that way. The same goes for all corporate legal status descriptors, which include: A.G., Co., Co. Inc., Corp., GmbH, Inc., LLC, LLP, L.P., Ltd., Pte., Pty., S.A., etc. 0-

The exact designation is chosen by the company and registered , so there is no standard format. However, most businesses choose not to use a comma.

You should always use a comma before "LLC" because it is an Acronym. The reason that commas are not used in front "Inc." or "Ltd." is because these are Abbreviations.

The AP Style Guide says never use it "even if it is included in the formal name." I think that's just lazy; take the time to find out the formal name and treat it the way it's set forth in the articles of incorporation.

I think, though, if you tallied all the commas and non-commas in the US, you'd get more non-commas, at least for the Corp., Inc., and LLC. Not sure about non-US tallies.

No comma before LLC according to current AP Style.

I disagree. If the company is incorporated with a comma (,) as part of its name, a comma SHOULD be used.

LLC isn't an acronym, it's an initialism.

Should I trust a post (immediately previous one) that is a run-on sentence?

Actually it's a comma splice.