Most of the time, in the U.S., we treat the company name as a single entity and use the singular verb. I find your example a bit jarring, and my wording would have been:
Fujitsu sends a newsletter to all subscribers once a month.
(Notice how I've added an article as well.)
Here's an example pulled from a news article that exhibits the use of the singular:
Polaroid announces range of Q Series tablets ahead of CES.
However, exceptions could be found on-line, such as on a UK website:
Polaroid Announce 4k Television
As they continue to branch out, offering products unrelated to film and instant photography to cater for an ever-changing market, Polaroid have announced a 4K television set.
I believe this is a BrEng/AmEng distinction. I'm guessing that some ELUers might find your original version more palatable than my modified version – although I believe both camps would include the added article.
This is one of those English issues that has more than one flavour, and you need to know your audience to choose the most aesthetically pleasing option.
The nice thing is, either answer is correct somewhere. So, if anyone ever corrects you, you can always say, "Oh, I forgot; I was wording that for a British audience," and you'll sound quite cultured and informed.