I named my puzzle game after a genre. The genre was trademarked.

I shipped a box-pushing puzzle game and called it what everyone calls that kind of game: a sokoban. You push crates onto targets, you can only push and never pull, one careless move leaves you stuck. The genre goes back to the eighties. The word felt about as ownable as "platformer."

It is not. Sokoban is a registered trademark. A Japanese company, Falcon, has held it since 2001, along with the rights to the original game Hiroyuki Imabayashi made in 1982. The puzzle type is generic. The name is not. I had built a product on top of someone else's word without ever checking whether it was theirs.

Google Play told me plainly. I got a notice: the app was being removed in the United States, Japan, and South Korea, here is the reason, and here is who filed the claim. Three of the largest markets a small game can hope for, gone in the storefronts where the trademark is enforced, still up everywhere else. The notice did its job. The problem was real and it was mine.

I appealed. Google's answer was honest about its own limits: they could not restore the listing on their own. The only thing that reopens those markets is the rights holder telling Google to drop the claim. That is not the platform being unfair, it is the platform refusing to overrule an intellectual property claim it is not party to. Reasonable, and also a wall.

So I did the only thing left on my side of the wall. I stripped every reference to the trademark out of the game and the store metadata, renamed the app to Box Push, and wrote to the rights holder. I explained that the infringement was not deliberate, that I had already removed everything, and asked if they would release the claim so the listing could come back.

Silence. No reply then, none since.

I want to be clear about something: I am not saying the company is in the wrong. They own the mark, the claim is theirs to make, and the mistake that started all of this was mine for not looking. Their silence is their right too. This is a lesson I earned, not a grievance I am owed.

The cost is the kind you only feel after you ship. The store name changed in an afternoon, but the package id is still com.dangnhh.sokoban, fossilized into the app forever, because a package id cannot be changed once it is live. Every analytics row, every ad campaign, every bit of early ranking was pinned to a name I had to walk away from. A name is the cheapest thing to pick at the start and one of the most expensive to replace later.

So now I check. Before a name goes anywhere near a store, I search the trademark registers for the exact word. Roguelike, metroidvania, battle royale, sokoban: some of these are free and some have a company behind them, and the only way to know which is to look. Ten minutes against three markets is not a hard trade once you have paid the other side of it.

The game is still restricted in those three storefronts under its old name. I have done everything I can do alone, which turned out to be everything except the one thing only the rights holder can do. From here the lesson is the whole return: check first, every time.