Sony's (NYSE:SNE) stock jumped 8% on April 8 after Reuters claimed that investor Daniel Loeb's Third Point was building an activist stake in the Japanese conglomerate. Loeb's hedge fund, which manages about $14.5 billion in assets, is reportedly raising capital to build a $500 million to $1 billion stake in Sony.

That's only equivalent to 1%-2% of Sony's enterprise value, but Third Point convinced Sony to make changes before. It took a 7% stake in Sony in 2013, pushed the company to make changes at its entertainment unit, and sold its stake with a 20% gain the following year.

Third Point's exit was notably premature, since Sony's stock rallied about 140% over the past five years on the strength of its gaming business. However, Sony underperformed the S&P 500 over the past 12 months as that core growth engine ran out of steam.

Sony's smartphone business continues to lose money, and its movie studio faces an uphill battle against Disney (NYSE:DIS), which recently closed its acquisition of Fox's media assets. Can Third Point force Sony to make tough decisions to streamline its business?

Taking aim at Sony Pictures (again)

Back in 2013, Third Point urged Sony to spin off its movie studio business. Sony rejected the idea, but cut costs at the unit to improve its profitability. This time, Third Point wants Sony to consider selling the unit again, claiming that Netflix and Amazon could be potential buyers.

Sony Pictures certainly struggled after Third Point's exit in 2014. It suffered a data breach which exposed personal emails and internal plans, a political controversy regarding The Interview, and the derailment of its tentpole Spider-Man franchise when The Amazing Spider-Man 2 missed box office expectations as the lowest grossing live-action Spider-Man film ever.

Sony eventually rebooted Spider-Man by signing a deal with Disney, which allowed the character to appear in Disney's Marvel Cinematic Universe films. It also expanded its corner of the Marvel universe with successful films like Venom and Spider-Man: Into the Spider-Verse.

But despite those core improvements, Sony's theatrical performance remains inconsistent. In the first nine months of fiscal 2018, Sony Pictures' revenue (11% of its top line) fell 2% annually. Venom gave its movie business a big boost in the third quarter, but that growth was offset by lower TV production revenues, which were throttled by lower licensing revenues in the US.

Last quarter the company warned that Sony Pictures faces tough growth prospects and "low profitability", but that it was conducting a "concentrated review" of each of its channels to boost the segment's profits. Those streamlining efforts indicate that Sony isn't interested in abandoning the unit yet, and upcoming films like Men in Black: International, Spider-Man: Far from Home, Charlie's Angels, and the Jumanji sequel could still attract plenty of moviegoers.

Examining the semiconductor and insurance units

Third Point also wants Sony to clarify how its semiconductor and financial service units, which generated 11% and 13% of its revenue in the first nine months of fiscal 2018 (which ended on March 31), respectively, fit with the rest of its businesses.

Sony's semiconductor unit generates most of its revenue by supplying image sensors to roughly half of all smartphones worldwide. This business enables Sony to profit from the smartphone market without an industry-leading smartphone brand.

This business flourished when smartphone sales were robust, but the saturation of the market and higher expenses (for the development of next-gen 3D camera sensors) throttled its profit growth. The unit's revenue stayed nearly flat annually during the first nine months, but its operating profit plunged 25%.

Third Point is also questioning the importance of Sony Life, the insurance unit that accounts for a large portion of its financial services unit. The unit's revenue and operating profit fell 11% and 15% year-over-year, respectively, during the first nine months of 2018 due to losses on its life insurance products and poor investments.

Third Point isn't pushing Sony to sell these two units, but reevaluating their importance (and possibly downsizing them) could streamline its business and improve its overall profitability.

But don't get your hopes up...

Sony hasn't been firing on all cylinders lately, but I doubt Third Point can force it to make massive changes. Sony didn't agree to Third Point's demands to sell Sony Pictures last time, when it held a 7% stake, so it's unlikely that it will do so this time with the fund holding a 1%-2% stake.

Investors shouldn't assume that Sony will radically change its business anytime soon. But they should recognize the issues with Sony Pictures, Sony Life, and its semiconductor unit -- and see if they improve over the next few quarters.