Rakuten did not immediately respond to a request for further comment.
On Wednesday, Lee maintained his midyear bitcoin price target of $20,000 — roughly double Wednesday's prices — and a year-end target of $25,000. Lee is the only major Wall Street strategist to issue formal price targets on bitcoin, although an increasing number of financial firms have published reports on cryptocurrencies recently.
Bitcoin three-month performance
Lee also pointed out that bitcoin's low for the year has typically occurred in the first two months of the calendar year. That was the case in six of the last seven years, he said.
Bitcoin was trading near $10,450 Wednesday morning, up about 2.9 percent for February but down nearly 21 percent for the year. The largest cryptocurrency by market capitalization plunged from a mid-December record high above $19,000 amid worries about heavy-handed crackdowns by regulators in different countries. In the last few weeks, bitcoin hit a low below $6,000 — its lowest since November — before recovering.
Historical performance of "alt-coins" such as Zcash and ripple after sharp drops also indicates investors should avoid them until late March, Lee said.
The market capitalization of all cryptocurrencies excluding bitcoin has nearly halved to around $270 billion from a high of $511 billion in early January, according to CoinMarketCap.
Recent headlines about major companies getting into cryptocurrencies could also help prices.
"In 2018, we forecast at least 3 major publicly-traded corporations to issue native digital tokens," Lee said. "Already three major companies have announced efforts within crypto-currencies, which demonstrate that corporations may be moving towards crypto-currencies before Wall Street has embraced them."
In addition to Rakuten, the examples Lee cited are:
- Japanese messaging app Line announced in late January that it would launch a new division called Line Financial that would let users exchange digital currencies.
- Starbucks' Executive Chairman Howard Schultz has hinted in the last two months about how the company may use blockchain technology for a consumer payments application. "I think blockchain technology is probably the rails in which an integrated app at Starbucks will be sitting on top of," Schultz said Tuesday on Fox Business. The comments echoed Schultz's remarks in January on the coffee company's earnings call.
In his report, Fundstrat's Lee also made more tenuous connections between two technology-related giants and cryptocurrencies.
"Facebook, we believe, likely announces a crypto-strategy this year," Lee said. He noted speculation that if the social media company went public today, it might be an initial coin offering that rewards users, rather than only stock investors.
Amazon.com could also apply a similar strategy, Lee said.
Neither company immediately responded to a CNBC.com request for comment Wednesday.
Mark Zuckerberg, CEO of Facebook, did say in an online January post that his company would look into cryptocurrencies this year.
Separately, LendEDU said Tuesday that 51.7 percent of Americans said they would use an Amazon-created virtual currency for purchases. That's according to an online poll conducted with Pollfish from Feb. 23 to Feb. 24.