In response to FOIA lawsuits, the Office of the Director of National Intelligence turned over two (!) stacks of FISC documents pertaining to Section 702 surveillance. One document [PDF] (from an ACLU lawsuit) reveals a tech company (whose name is redacted) refused to hand over (or provide access to) communications requested with a Section 702 order. This order was issued in 2014, so it's a post-Snowden challenge. The end result -- determined with almost zero participation from the tech company -- is an order from Judge Rosemary Collyer demanding the tech company produce the records.
Discussed along the way to this conclusion are several things, including the NSA's problems with the Section 215 collection. There are also discussions about the adequacy of the NSA's minimization processes, meant to protect the privacy of US persons caught in the agency's internet dragnet. Unfortunately, we're not able to see much of this discussion, thanks to the opinion being heavily-redacted.
But we may be one step ahead of the mystery tech company, which had to fight this legal battle completely blind. All arguments and evidence were provided by the government, in camera and ex parte. The tech company was apparently allowed to submit its arguments, but was otherwise sidelined by the national security nature of the legal proceeding.
The opinion notes that the ODNI had issued a new 702 directive in 2014, presumably expanding the NSA's collection powers, which seems like a really odd decision post-Snowden. This is apparently what the tech company challenged. There's not much else that can be gleaned from the court's discussion of the expanded powers and their effect on the Fourth Amendment, other than it disagrees with the tech company's assessment. At one point, the court states "This argument is simply not supported by the facts" before heading into six fully-redacted pages apparently discussing the facts that don't support the company's arguments.
The court also finds, despite evidence to the contrary, NSA "incidental" collection of US persons' communications does not happen "frequently, or even on a regular basis." Any discussion of what the court feels is an acceptable amount of violations is, again, hidden under page after page of redaction.
To sum up, the court concludes that even if it's a close call on the Fourth Amendment (and even if the company had standing to bring this challenge), the national security purpose of the collection outweighs most possible privacy concerns. It expresses a great deal of faith in the NSA's internal oversight -- which seems odd considering the admissions by the NSA about its collection tactics in other released documents, including the fact that it relies almost completely on self-reporting and spot checks to minimize use of incidentally-collected US persons' communications.
The good news is that the NSA's inability to stop incidental collection resulted in the shutdown of the "about" collection. The other good news is some mystery company took a strong stand to protect its users' privacy. The downside, however, is the challenge failed. Worse, it appears the NSA's other 702 collection methods are still capable of grabbing US persons' communications and its internal oversight hasn't gotten much better over the years.