If it happens, Alphabet will move to the head of the class just five months after Google reorganised itself under the holding company.
The Silicon Valley rivals could trade places as early as Friday, given how rapidly the financial gap between them is narrowing. At the end of trading on Thursday, Apple's market value stood at $522 billion; Alphabet was worth $515 billion.
That's a dramatic swing from where things stood just 13 months ago. Apple then boasted a market value of $643 billion, almost twice Google Inc's $361 billion.
Hoping to provide greater clarity into the performance of its many holdings, Alphabet Inc said it would report financial results under two segments, Google and "Other Bets," when it releases fourth-quarter earnings on Monday.
Since the August 10 announcement, Alphabet's stock price has climbed almost 13 per cent, closing at $748.30 on Thursday.
Under Google, Alphabet will report the results of its main internet and related businesses such as search, ads, maps, YouTube, Android, Chrome and Google Play, and hardware products such as Chromecast, Chromebooks and Nexus, as well as its virtual reality offerings.
"Other Bets" will detail Alphabet's other businesses, including Access/Google Fiber, Calico, Nest, Verily (formerly known as Google Life Sciences), GV (once known as Google Ventures), Google Capital and X, better known as Google X.
Alphabet said there would be no changes to its consolidated financial reporting but some changes would be made to how it breaks out revenue.
Investors and analysts had praised the move to the Alphabet structure as a shift toward greater transparency and fiscal discipline when it was announced in August.
It will provide investors their first detailed peek into the finances of the parts of Google outside its highly profitable search engine.
In a blog post announcing the changes, Alphabet's chief executive, Larry Page, said the change allows the company to take the "long-term view" of its holdings and invest "at the scale of the opportunities and resources we see."
"Fundamentally we believe this (structure) allows us more management scale, as we can run things independently that aren't very related," said Page.