First article on Reuters mentioned Apple and Samsung, among others, as companies that will invest in this IPO. The article said that around ten companies, including Apple, Samsung, and Intel, engaged in discussions with Arm to potentially secure anchor investments for its anticipated IPO, aiming to bring in influential backers for the offering. Recent reports also indicated that Arm was in talks with U.S. chip designer Nvidia to potentially serve as an anchor investor for the New York listing. Sources suggest that once Arm goes public, Apple, Samsung, Nvidia, and Intel are all poised to invest in the company. SoftBank, the parent company of Arm, is expected to formally submit its application for the IPO to the U.S. Securities and Exchange Commission later this month. Amazing news in my opinion, to have such support from the biggest companies in the world. If they decided to support it, then it means that they for sure have a good plan. 
Second article on this matter, which I found on Investing, said that Amazon is also in talks to invest in Arm IPO. Now, if also Amazon gets involved, then I don’t see a reason why I wouldn’t follow them. But since I don’t know much about the company. I decided to check what it’s all about.
Various sources on the internet provided me with info, that Arm is Headquartered in Cambridge, England, and is a British semiconductor and software design company primarily focused on designing ARM processors (CPUs). Additionally, it develops various chips, offers software development tools like DS-5, RealView, and Keil, and delivers systems, platforms, and system-on-a-chip (SoC) infrastructure alongside software. It also functions as a holding company, holding shares of other enterprises. Since 2016, the company has been under the ownership of the Japanese conglomerate SoftBank Group.
Although ARM CPUs initially appeared in the Acorn Archimedes, a desktop computer, contemporary systems mainly consist of embedded systems, particularly ARM CPUs integrated into nearly all modern smartphones. Processors built on Arm designs, either licensed or designed by licensees adhering to ARM instruction set architectures, are employed across a broad spectrum of computing devices. Arm boasts two lines of graphics processing units (GPUs), namely Mali and the newer Immortalis, which includes hardware-based ray-tracing capabilities. In the realm of servers, Arm's chief CPU rivals include IBM, Intel, and AMD, while in the mobile sector, Arm no longer faces any competition.
I am honestly amazed by the company, so I will for sure be ready in September when they will have an IPO. It is for sure worth to at least follow the company, if not investing into it. 
[1,2] Forward-looking statements are based on assumptions and current expectations, which may be inaccurate, or based on the current economic environment which is subject to change. Such statements are not guaranteeing of future performance. They involve risks and other uncertainties which are difficult to predict. Results could differ materially from those expressed or implied in any forward-looking statements.