# 4.4 Soulbound Token (SBT)

Since Vitalik, E. Glen Weyl, and Puja Ohlhaver jointly proposed the idea of SBT in May of this year, SBT has gained a widespread acceptance and application, including Vitalik's proof of stake or Binance's BAB, both of which have significantly accelerated the development of SBT.

We think SBT has a high application value since, just at the marketing level, its will aid projectss in better understanding their users and more effectively locating prospective users. SBT will be the few tangible display of user profiles and DID in the crypto industry.

The absence of a unified standard and real-world application scenarios are the two biggest issues facing SBT development, which is still in its early stage.

In the absence of a universal standard of SBT, Bound Wallet will promptly adopt a variety of protocols used by well-known SBT projects and give consumers a thorough view of all SBT they own.

Meanwhile, RPD will issue SBT to our users based on their in-game and on-chain activities.

At last, by labeling SBT, Bound Wallet will establish the largest SBT-label pool. This label pool will assist projects in acquiring suitable users through intelligent recommendation. Those projects have to pay for this marketing service.
