With apologies to the OP's narrow original question, given that questions involving distinct legal issues and non-US jurisdictions are being closed as duplicates, there are some points that I think need to be mentioned here.
To summarize: given the lack of clear legal authority on copyright claims over patent materials in most countries, any blanket assertions that such claims are or aren't valid should be treated skeptically. So while the theoretical issues here are fun to talk about, anyone who needs to know their potential level of risk (as a defendant) or viability (as a plaintiff) should contact their friendly neighborhood IP attorney.
I. This is a pretty hypothetical question
The question of whether there are enforceable copyrights in patent application materials is almost entirely theoretical. Copyright cases based on patent specifications are vanishingly rare, and in the US (and many other countries), binding legal authority on them appears to be nonexistent.
(That said, speaking of things that should not be taken seriously: AFAIK nobody has really attempted to conduct a comprehensive search for this kind of patent-copyright litigation, and even in the US where records are comparatively accessible, trial-court cases that don't reach a final judgment can be very hard to find. So my assertion that they are "vanishingly rare" should also be taken with a healthy dose of salt. Some cases may be quietly settled, as happened for example in at least one of the rash of suits over "prior art" documents that were brought in the US in the early 2010s. The most that can really be said is that no such case appears to have ever proceeded as far as an appellate ruling.)
Indeed, even statements by government bodies in this area often have to be taken with skepticism. The USPTO, for example, does not have rulemaking authority over copyright law. Thus, the MPEP/CFR sections sometimes cited with regard to copyright assertions -- even supposing that they are not, as they appear to be, based on pre-1990 US copyright law that required copyright to be expressly asserted -- would have little if any bearing on a copyright case in the US federal courts.
II. There are a lot of different copyrights that could be involved
The potential copyrights in a patent application may vary greatly. For example, the questions of the ownership and allowable scope of use would be very different with respect to:
1) specific boilerplate paragraphs used by a law firm (as in the original
2) a specification cooperatively drafted by a patent agent and
group of inventors for the specific purpose of submission and
publication to a patent office,
3) drawings by a third-party professional illustrator that are used
in a patent application with the illustrator's consent, and
4) third-party text or drawings incorporated in a patent application
or grant without the copyright owner's consent.
Looking at #1, notably, at least one knowledgeable US observer has concluded, based on the unexpected difficulties that defendant law firms faced in defeating copyright claims based on prior art documents, "[t]he use of copyrighted materials to fulfill legal obligations in governmental proceedings is most likely fair use, but it’s not the 'slam dunk' defense that many once thought it was." Whether that would extend to something like one firm copying another firm's boilerplate is unclear.
Looking at the example of drawings, the US doctrine of "fair use" and the apparent UK exception for "disseminating information" would excuse most patent-scraping operations even where the patents include copyrighted illustrations. But even under those US and UK doctrines, it's far from clear that a company would be free to (for example) reuse suitable drawings from a competitor's patent application in its own proprietary materials, particularly if the company's purpose were merely to save on illustration costs rather than to provide any information about the competitor's application. And many countries do not provide the relatively generous copyright exceptions that the US and UK do.
III. There is a lot of variation between countries
The legal principles that would apply to any such claim vary dramatically from one country to another. (Wikipedia provides a very limited survey.) Given the lack of actual litigation in this area, it's impossible to know how significant those variations are.
For example, it seems that a copyright claim based on an asserted copyright in an EPO patent application might fare very differently in different EPO member states, e.g.,
- Switzerland (where the Copyright Act expressly excludes "patent
specifications and published patent applications"),
- the UK (where
the law apparently provides a general "disseminating information"
- Germany (where the DPMA construes the
Copyright Act (secs. 5, 62) to exempt republications of patent
documents, but only as long as the copier follows the Copyright Act's
stringent requirements, e.g. that the document not be modified).