what if bought marketplace content isnt developed any further and the author refuses to call back

[=Two-faced;689865]
[MENTION=434] [/MENTION]

Btw, is there way to not provide a source code in your Marketplace plugin or BP assets? What is you don’t want to reveal your rare math algorithm or something?
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Then don’t sell it, as simple as that.
There are plugins with a closed source code but normally they are for the products which go beyond plugin itself, like Substance or SpeedTree. I wouldn’t risk buying a plugin, without source code, from non-established software company without a reputation and being on a market for a few years.