Obelisk, a startup that aims to offer alternative mining equipment for the Siacoin ($SC) protocol, has proposed code would give those running the software the option to exclude Bitmain's ASICs by changing the rules so the machines are no longer compatible. This will give the Sia community the ability to fork and could invalidate all non-Obelisk Siacoin ASIC miners on the forked chain. The news is notable as it showcases how cryptocurrency communities are responding to the expanding business interests of Bitmain, the China-based mining giant that is seeking to raise an initial public offering (IPO). Should Siacoin be successful it wouldn't be alone in its efforts to curtail Bitmain's expansion. One of the world's largest cryptocurrencies, the privacy-oriented Monero ($XMR), implemented code to remove Bitmain ASICs earlier this year.