SpaceX stock falls as Starship's test flight slips to Sept. 28, retail investors sell shares

SpaceX ( SPCX ) fell over 2% on Friday, paring its gain for the week to around 1%, as investors weighed a delay to the company's first orbital Starship flight against a fresh round of bullish commentary from one of its largest backers this week.

The pullback came after SpaceX pushed back the 14th test flight of its Starship vehicle by six days, to Sept. 28 from an earlier Sept. 22 target. The mission from Starbase in South Texas is the program's first orbital flight: The upper stage is slated to reach about 275 kilometers, complete approximately six orbits over a nearly 10-hour mission, and deploy 26 Starlink V3 satellites, each adding a terabit per second of capacity to the network.

The Super Heavy booster will attempt an offshore landing while the ship performs a controlled splashdown in the Pacific west of Chile. SpaceX said that no "Mechazilla" catch is planned this time, walking back earlier expectations.

A successful flight matters to SpaceX's bull case, underpinning the economics of Starlink deployment, commercial launch, and the company's lunar and Mars ambitions.

Friday's slip was a reminder of how quickly sentiment can turn on a newly public name. Per Barron's , JPMorgan noted that around $570 million in retail selling occurred over the past three weeks, with retail investors taking $250 million off the table this past week, the largest weekly decline the bank has ever seen.

On the flip side, billionaire investor Ron Baron, whose Baron Capital holds about $25 billion in SpaceX shares, remains bullish on the stock. In a CNBC interview , Baron laid out an aggressive case for the satellite business, which he estimates generates nearly $18 billion in revenue today.

"I think Starlink alone could be a trillion dollars in revenue in 10 years," Baron said. "And if you look at the margins, $700 billion, $800 billion of EBITDA. And you put a multiple on that, that would support a $14 trillion, $15 trillion valuation."

Baron also weighed in on the recurring question of whether SpaceX and Tesla ( TSLA ) might one day combine. "Whatever you decide ... is what I'm going to support," Baron said he told Musk.

Musk has stoked that speculation himself. Speaking at the All-In Summit , the CEO called it a fair question whether the two companies would stay separate, given how closely they collaborate.

"With all this collaboration, on so many levels, who can imagine what action one might take when there's so much close collaboration in so many areas," he said.

Yahoo Finance reached out to SpaceX regarding Musk's merger comments but did not immediately hear back. It is not the first time the idea has surfaced; reports suggested Musk had openly discussed a possible merger before SpaceX's June IPO.

Pras Subramanian is Lead Transportation Reporter for Yahoo Finance. You can follow him on X and on Instagram .