The investment was part of a $10.1 million fundraising announced by the New York-based company last month, which remains open for “value-added investors.” Other backers include Japan’s Rakuten ($5m) and venture capital firms DCM ($3.5m) and FirstMark Capital ($1.6m).

Mack’s involvement was not disclosed, and I’ve not been able to find any other reference to the former Wall Street titan making this type of investment. The only exception may be Lending Club, an online peer-to-peer loan platform that added Mack to its board of directors back in April.

It’s also unclear how Mack got involved with AHAlife, which offers up luxury lifestyle products that are curated by influencers like fashion expert Tim Gunn, chef Daniel Boulud and model Petra Nemcova. One possibility could be his past relationship with Pequot Capital, given that FirstMark Capital began life as Pequot’s in-house venture capital arm. Or perhaps he knew AHAlife co-founder Matt Wilkerson, back when Wilkerson was a media and telecom banker with Morgan Stanley.

I’ve left message for MAck and AHAlife for comment, and will update this post if they respond.

Update: Just spoke with AHAlife CEO Shauna Mei, who tells me that Mack’s family office invested in her company’s seed round. Also, John’s son Stephen is an AHAlife curator. “John just really likes the company, and we were very pleased that he decided to invest,” Mei says.

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