Interlay will start the "tokenized bitcoin" based on the Polkadot blockchain.

Startup Interlay, which received funding from Web3 Foundation, will launch "tokenized bitcoin" PolkaBTC based on the Polkadot blockchain in the first quarter of 2021.
Interlay developers said that PolkaBTC will be provided with bitcoin at a ratio of 1:1. The new digital asset is being created as an alternative to tokens WBTC and tBTC, operating on the basis of Etherium. PolkaBTC will not be controlled by a centralized authority and will be resistant to censorship similar to the Bitcoin network. The BTC Parachin will be initially managed by a decentralized network of community members, which includes organizations and individual users.
An internal Polkadot token (DOT) will be used as collateral for the PolkaBTC. Any user will be able to perform the "storage" function by blocking DOT tokens as a pledge. To do this, you only need to have a Bitcoin wallet and Polkadot, and a certain amount of DOT. Users will be able to transfer PolkaBTC to others or use it in decentralized applications based on Polkadot. To exchange for PolkaBTC bitcoins will be burned in a BTC parachine. PolkaBTC can stay in the Polkadot network for an indefinite period of time, and you can exchange them for the bitcoin at any time.

The first PolkaBTC alpha testing is scheduled for November 2020, and beta testing with support for the necessary functions will be held in January next year. The launch of the main network is expected in the first quarter of 2021. In addition, the management of Interlay said that it intends to integrate PolkaBTC with the projects Equilibrium, Moonbeam and Polkaswap, created on the basis of the blockcheck Polkadot.

In spring, Keep Network and Summa startups also developed "tBTC tokenized bitcoin". It was designed to provide access to decentralized funding on the Etherium without the need to exchange BTC for ETH. However, a few days after tBTC was launched, its emission had to be suspended due to a detected vulnerability.