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The designer goes on to explain that he created designs for the Oldboy poster at the request of an ad agency that went on to make "an insultingly low offer" when his work was selected for use. "I tried to negotiate but they refused. I make the same amount of money in a single day as a photo assistant as what they offered, and I had worked on these almost exclusively for two months," he wrote.

"We never signed any contracts or work-for-hire agreements and I certainly never agreed to donating or selling any copyright of my work without a licensing fee," Garcia wrote, adding, "I never even got paid the peanuts they owed me [for the original design pitches]." Despite that, the images and concepts he created for the agency were used, he explained, with the agency threatening legal action against him when he complained.

What prompted the open letter, he continued, was the fact that his images then appeared on Lee's own social media feeds. "I couldn’t believe that you had been using and claiming copyright on three of those very same posters I designed," Garcia wrote. "I just couldn’t believe it. I perceive you as an advocate of the arts and artists and have a sinking feeling that you are as much of a victim in this as I am."

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Response to the letter has been overwhelming, Garcia explained to THR via email. "My in-box is being inundated with support from the design community," he said. "This seems to happen far too often and it simply isn't right." He also answered a nagging question from the original letter: "Everyone is asking why I don't name the agency and the answer is simple. Spike knows exactly who I am referring to."

Garcia said that the objective of the open letter was simply "to reach [Lee] with the truth so that he can help me instead of taking legal action. I don't want to sue anyone, it's not in my nature, but if that's what it comes down to, so be it. I'm thrilled he liked the posters and hope they continue using them, but I need to be renumerated."