The data firm TokenAnalyst posits that Goliath bitcoin investors simultaneously jumped into the market, leading to this week's spike in bitcoin's value.

The "whales" acted as a fuse for transactions from thousands of small accounts, one of the firm's founders said.

"It definitely seems like there is intent behind this," he said.

Bitcoin's inexplicable spike of more than 23% on Tuesday to above $5,000 a coin led to dozens of theories as to what drove the rally, including a wacky explanation that pinned it on an April Fools' Day gag.

Another theory, from the data firm TokenAnalyst, posits that Goliath-size bitcoin investors intentionally and simultaneously jumped into the market, which acted as a fuse for transactions from thousands of small accounts.

Sid Shekhar, a cofounder of the London-based TokenAnalyst, has been tracking the moves and noticed the anomaly. For example, he said, one Tuesday bitcoin transaction that flowed from an external whale account to an account on the BitMex exchange was valued at $7.5 million.

By tracking the flow of transactions on the blockchain into the bitcoin storage accounts, or wallets, on the exchanges, Shekhar said his firm was "able to see some of this stuff before it happened."

"We saw a few large whale movements of funds, then a concerted inflow into multiple exchanges from whale wallets, and then we were seeing a virtuous cycle" from the flurry of tiny accounts that followed suit, he said. The small trades were triggered by both market algorithms and retail investors, he added.

"The whales didn't move it all by themselves, but they were the first domino," he said. "As soon as that first domino fell, we saw a bunch of programmatic action based on momentum, which led to more and more price action."

The whales had been accumulating bitcoin over the past few months, building up a large-enough stash to then simultaneously flow into multiple exchanges such as Binance and BitMex, he said.

"It's unusual to have been done in concert over so many exchanges," he said.

Shekhar says he and his team are trying to link the funds to their addresses to track down who the whales are.

"It definitely seems like there is intent behind this," he said. "Players who have been hoarding up bitcoin wanted to pump up the value of their holdings."

Total on-chain inflows into major crypto exchanges compared with the exchange-reported volume. TokenAnalyst

A close-up of one specifically large whale transaction. TokenAnalyst