Bitcoin 

BTC

$18,125

 jumping to $39,000 has already activated large-volume investors this week, the latest data shows.

Analyzing whale behavior, on-chain monitoring resource Whalemap revealed accumulation underway at levels above $36,000.

This week’s BTC price “triggered” whales

Identifying clusters of whale bids, Whalemap uncovered what appears to be renewed market confidence among those with some of the largest BTC balances — between 100 BTC and 10,000 BTC.

“Recent prices triggered whales to accumulate Bitcoin,” researchers summarized on Twitter Tuesday.

According to cluster data, whales now own 330,000 BTC bought at spot prices between $36,000 and $38,000.

Overall, the portion of the BTC supply per whale wallet is now at its highest in a decade, data from on-chain analytics firm Glassnode uploaded to Twitter by popular account Priced in Bitcoin shows.

This comes despite the vastly larger Bitcoin user base compared to the largest cryptocurrency’s early days. 

Trader and analyst William Clemente, meanwhile, described last week’s whale activity as “fairly heavy” buying.

Exchanges see new influx of BTC this weekend

The results run in contrast to a decreasing buying trend, which began in the second half of January.

Related: Bitcoin market cap dominance hits 2-month high as altcoins struggle

As Cointelegraph reported, exchanges returned to seeing greater outflows than inflows in recent weeks, despite spot price action putting in lower lows.

In the past few days, however, exchange users have conversely sent BTC to their accounts as BTC/USD has risen to its highest levels in two weeks.

The 21 platforms monitored by on-chain analytics firm CryptoQuant saw their balance increase from 2.357 million BTC on Jan. 29 to 2.377 million BTC on Jan. 31, the latest date for which data is currently available.

Whales may not actively use exchanges for larger buys, particularly if they are in a position to perform over-the-counter trades or purchase coins directly from miners.