tenki.jp already shared cookie data with a long list of ad companies. This update adds SoftBank Corp. to that list. SoftBank will receive your device information (country/region, network conditions) and your browsing history, and use it to fine-tune LINE Yahoo ads. It is one more company holding a record of what you look at on the site. The impact is bounded because the data types are similar to what other partners already get, and an opt-out link is provided.
“| ソフトバンク株式会社 | デバイス情報(国・地域情報、通信環境など)、履歴情報(閲覧履歴など) | LINEヤフー広告の配信改善のため”
What you can do — If you don't want SoftBank using your browsing data for ads, opt out at https://www.softbank.jp/privacy/personaldata/utilization/ads/ . You can also opt out of LINE Yahoo ad targeting at https://btoptout.yahoo.co.jp/optout/index.html .