Citron Research's Andrew Left, who gained attention for successful bets against companies including Valeant Pharmaceuticals, reiterated his negative call and $45 price target on Motorola Solutions.
Left confirmed he is currently short shares of the communications equipment maker in an email to CNBC.
A Motorola Solutions decline to $45 would represent a fall of nearly 50 percent for the shares.
"We continue to believe MSI will play a materially smaller role in the evolving public safety market in the medium-term versus its dominant position today," Left wrote in a new blog post about the company Wednesday. "It is only a matter of time before the market withdraws MSI's high-growth tech stock multiple, and it is repriced for what is left of its business. Losing handset sales will be the initial blow to MSI and service revenue will soon follow."
Motorola Solutions shares were slightly higher in late trading Wednesday. The stock was up 4.3 percent year to date through Tuesday versus S&P 500's 9.5 percent return.
This wasn't the first time Citron expressed a bearish view on Motorola Solutions shares. He predicted the communications equipment maker would face pricing pressure from the government in February.
A Motorola Solutions spokesperson sent the following statement for this story:
"Citron's latest attack is another transparent attempt by a self-interested short-seller to profit, at our shareholders' expense, by manipulating Motorola Solutions' stock price.
Based on numerous reports published by credible third parties, even in the last week, we are encouraged that investors recognize Citron's allegations as false, misleading and demonstrative of a clear misunderstanding of our customers, industry and products.
We are confident that we have the right strategy, products and solutions in place to continue creating shareholder value. We are proud to be a core member of the AT&T team delivering FirstNet with our broadband-enabled devices, mobile applications, software and services."