What is Reddit's opinion of The Texas Chainsaw Massacre (1974) Movie Poster 24x36 This is a Certified Print with Holographic Sequential Numbering for Authenticity.?
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The Texas Chainsaw Massacre (1974) Movie Poster 24x36 This is a Certified Print with Holographic Sequential Numbering for Authenticity.

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I did not literally see the copyright notice on the company credits page on imdB, but that page says it's "Vortex (as A Vortex/Henkel/Hooper Production)" which would be one place to start.

I didn't see a copyright notice on this purported copy of the original movie poster, but it says "A Bryanston Pictures Release" - but they're listed as a mere distributor on the above imdB page.

The most straightforward way to start is to instead rent a copy and look for the copyright notice that is probably shown at the end of the original credits.