Shares of

(NASDAQ:

) were trading up more than four percent in Thursday's pre-market session. Tesla CEO Elon Musk tweeted a teaser about a mysterious unveiling of what he called the "D" on October 9.

Following the tweet, Global Securities reiterated it "Build Position" sentiment for investors with a 12 to 18 month horizon. The firm also noted

(NYSE:

) stands to benefit from the announcement and the rumor that

(NASDAQ:

) invest in Tesla's gigafactory may be accurate. Shares of Mobileye were last up 2.6 percent, or $1.40, at $54.39 early in Thursday's session. However, Global Securities does not expect an Apple investment to be part of the October 9 announcement. Instead, the firm thinks it is more likely that Tesla will only show off the ability to operate the cars with the iPhone 6, i.e., open doors and turn the Model S on. About an hour after posting the tweet, Musk

, "I love the Internet. Comments had me literally ROFL. No, it wasn't intentional. Glad I didn't mention the other letter!"

Tesla opened up about 5 percent higher Thursday. It was last up 3.33 percent at $248.35. The stock is down 12 percent, or $35, over the past month, but up more than 60 percent year to date.