And in the end, Lavery said, that fact that blu's sales are very small compared with Reynolds' overall business "makes it quite possible that Imperial was more interested in owning blu than Reynolds was."
The news agency Reuters, citing a source familiar with the situation, reported Tuesday that Imperial Tobacco insisted that blu be among the assets it was buying in the deal.
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Miguel Martin, president of Logic, the No. 2 e-cig brand after blu, told CNBC.com, "My quick read on it is that I don't know that Reynolds felt that they had to have blu. My sense is they felt they didn't have to have it."
"It wasn't important to them, and it was to Commonwealth," he said, using the name of Imperial's U.S. sales division. "I think Reynolds feels comfortable going it alone with Vuse."
Martin said he doesn't believe that blu's change of ownership will affect Logic's sales.
"From my point of view, I don't know it changes anything," Martin said. "I don't know that it's better off fighting blu under the Commonwealth flag than under the Lorillard flag."
Blu has lost market share to Logic in recent months, according to both Martin and Lavery.
Regardless of who owns blu, the brand will continue facing future declines in market share due to competition from Logic and ongoing "disruption" in the still-young industry, Martin said.
He said companies such as Logic, which do not sell traditional combustible tobacco products, may have an edge with getting shelf space while competing with blu because convenience stores keep a larger percentage of the sale price with their products than they do with the e-cig brands sold by traditional tobacco companies.
Also, Blu, like other e-cig companies that sell replaceable nicotine liquid cartridges, are now facing competition from the accelerated growth of so-called open system vaping devices, said Cynthia Cabrera, executive director of the Smoke-Free Alternatives Trade Association.
Unlike "ciga-likes" such as blu, whose shape resembles a traditional cigarette and whose manufacturers sell disposable or refillable cartridges of nicotine liquid of their own brand, open-tank systems allow users to refill the devices with a nicotine liquid of their choosing. "Vaping" shops often sell a wide range of such liquids, with different levels of nicotine and a variety of flavors.
Bonnie Herzog, a tobacco analyst at Wells Fargo, noted earlier this year that the open system sector is growing twice as fast as the overall e-vapor category, which includes traditional e-cigs like blu. Herzog said users of open-system vaping devices spend less money on their habit than people who buy traditional branded e-cigs.
In terms of innovation, "the ciga-like category is really not where it's at right now, where it is is open vapor," Cabrera said.
Still, she doesn't expect Imperial to let blu lose market share to open system products without a tough fight.
Big traditional tobacco companies "will use every competitive and regulatory means possible to squeeze out the little guys, the innovative guys, because those aren't their products," Cabrera said. "I do have concerns about that."
—By CNBC's Dan Mangan