A study of tens of thousands of YouTube videos and Telegram messages suggests that crypto airdrops increasingly depend on weeks or months of unpaid online work. Researchers describe the phenomenon as “post-speculative finance”, in which participants do not simply bet on an asset’s future value but actively help create it.

The promise of free cryptocurrency can come with a substantial hidden cost: time, effort and, in some cases, money spent pursuing a reward that may never arrive.

That is the conclusion of new research led by the University of Leicester, which examines the growing role of crypto airdrops in blockchain projects. These distributions of digital tokens are intended to attract users and reward participation, but…