SoftBank, a Japanese conglomerate and investment firm, is seeking a retreat from the U.S. wireless market, according to The Wall Street Journal.

The company, which recently gained about 25% of T-Mobile US’ common stock following the operator’s acquisition of Sprint, is negotiating the sale of a significant portion of its stake to T-Mobile US' majority shareholder Deutsche Telekom. The deal would give the German company near total control in the recently combined company and effectively end SoftBank’s aspirations in the U.S. wireless market. SoftBank invested $22 billion in 2012 to gain a controlling stake in Sprint and set some lofty goals to make it the No. 1 carrier in the market at the time.

Sprint’s challenges proved to be too much to overcome, despite SoftBank’s heavy and direct involvement in the business. SoftBank began tightening the purse strings within a few years of its initial investment and effectively admitted that Sprint could not dig itself out of a hole on its own.

SoftBank Chairman Masayoshi Son started exploring a combination of Sprint and T-Mobile in 2014, and again in 2017, but that quest to merge didn’t lead to an agreement until 2018. A bitter, hard-fought battle followed for the next two years before the companies became one last month.

SoftBank’s eight-year involvement in the U.S. wireless market has been a long slog, but Son maintains that the investment paid off in financial terms. Sprint was also sagged with nearly $37.37 billion in total debt at the end of 2019, and it lost $25 billion during the previous decade.

While T-Mobile US is undeniably better positioned for growth and profits, SoftBank’s mounting losses on massive investments in other businesses is forcing it to seek the sale of assets to improve its finances overall. 

SoftBank’s main businesses reported $13 billion in total annual losses and it lost another $18 billion on its investments. The company has pledged to sell $41 billion in assets to boost liquidity and fund a major stock-buyback program.

While SoftBank is precluded from selling most of its stake in T-Mobile US for the next four years per terms of the merger agreement, the proposed sale would occur as a secondary offering and in coordination with Deutsche Telekom, which is also party to those same stipulations, according to CNBC.

T-Mobile US’ current market cap sits at $125.92 billion and SoftBank’s total stake in the company is valued at nearly $31.5 billion.