That’s not a quote from the statute. Under INA 214(b), an immigrant entering the country is presumed to have immigrant intent unless he can prove that he intends to stay only temporarily and plans to leave. This is a condition of entry on any non-immigrant visa, including the H1-B.
Ordinarily, applying for permanent residency would signal immigrant intent, which would be a violation of the H1B. The INS later created “dual intent” as a legal fiction that says that applying for a green card doesn’t, by itself, create a presumption of immigrant intent. Congress codified this narrow exception in the 1990s—but never eliminated the requirement that H1Bs have non-immigrant intent. See section 205(h) on PDF page 66: https://www.justice.gov/sites/default/files/eoir/legacy/2009...
> (h) The fact that an alien is the beneficiary of an application for a preference status filed under section 204 or has otherwise sought permanent residence in the United States shall not constitute evidence of an intention to abandon a foreign residence for purposes of obtaining a visa as a nonimmigrant described in subparagraph (H)(i) or (L) of section 101(a)(15) or otherwise obtaining or maintaining the status of a nonimmigrant described in such subparagraph,
When someone here on an H1B applies for a green card, the government winks and says “we will both pretend that you still intend to go back home.” Their legal rights are limited to this indulgence. If they signed an affidavit swearing that “I definitely intend to immigrate here permanently and abandon my residence in my home country” the government might well be forced to kick you out.