{
  "timeline": [
    {
      "date": "1897/1",
      "category": "会社設立",
      "region": "",
      "importance": 3,
      "event": "住友伸銅場を開設し銅電線製造を開始",
      "detail": "住友本店が日本製銅を買収し大阪市北区安治川上通に開設、銅電線などの製造を開始",
      "significance": "住友電工の源流。非鉄金属と電線の双方にまたがる事業の原点",
      "source": "有価証券報告書"
    },
    {
      "date": "1899/1",
      "category": "組織再編",
      "region": "",
      "importance": 1,
      "event": "大阪製銅を買収、中之島分工場を開設",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1900/1",
      "category": "",
      "region": "",
      "importance": 1,
      "event": "被覆線の製造開始",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1909/1",
      "category": "",
      "region": "",
      "importance": 1,
      "event": "通信用ケーブルの試作開始",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1911/1",
      "category": "組織再編",
      "region": "",
      "importance": 3,
      "event": "住友伸銅場から電線製造業を分離し住友電線製造所を設置",
      "detail": "あらゆる電線ケーブルの製造能力を確立",
      "significance": "電線専業メーカーとしての立ち上がり。現社名の直接の前身",
      "source": "有価証券報告書"
    },
    {
      "date": "1916/1",
      "category": "設備投資",
      "region": "",
      "importance": 1,
      "event": "エナメル線の製造開始、大阪製作所の地に新工場完成",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1920/1",
      "category": "組織再編",
      "region": "",
      "importance": 3,
      "event": "住友総本店から独立し株式会社住友電線製造所として設立",
      "detail": "",
      "significance": "株式会社化による近代企業化。住友財閥傘下での独立経営開始",
      "source": "有価証券報告書",
      "amount": "資本金1,000万円"
    },
    {
      "date": "1931/1",
      "category": "",
      "region": "",
      "importance": 2,
      "event": "イゲタロイ（超硬工具）製造開始、東海電線に資本参加",
      "detail": "東海電線は現・住友電装",
      "significance": "超硬工具事業への進出と、後の基幹子会社・住友電装の源流獲得",
      "source": "有価証券報告書"
    },
    {
      "date": "1932/1",
      "category": "",
      "region": "",
      "importance": 1,
      "event": "耐酸ニッケル線など特殊金属線の製造開始",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1937/1",
      "category": "企業買収",
      "region": "",
      "importance": 1,
      "event": "東海護謨工業（現・住友理工）に資本参加",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1939/1",
      "category": "組織再編",
      "region": "",
      "importance": 2,
      "event": "社名を住友電気工業株式会社に改称",
      "detail": "",
      "significance": "電線専業から総合電気工業への事業領域拡大を社名で示す",
      "source": "有価証券報告書"
    },
    {
      "date": "1941/1",
      "category": "設備投資",
      "region": "",
      "importance": 1,
      "event": "伊丹市に伊丹製作所を開設",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1943/1",
      "category": "",
      "region": "",
      "importance": 1,
      "event": "防振ゴムの製造開始",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1946/1",
      "category": "組織再編",
      "region": "",
      "importance": 1,
      "event": "東京・名古屋・福岡に拠点開設",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1948/1",
      "category": "",
      "region": "",
      "importance": 1,
      "event": "焼結製品の販売開始",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1949/1",
      "category": "株式上場",
      "region": "",
      "importance": 3,
      "event": "東京・大阪・名古屋各証券取引所に上場、ワイヤーハーネス事業・架空送電線工事部門に進出",
      "detail": "",
      "significance": "上場による資本調達基盤の確立と、現在の主力事業ワイヤーハーネスの起点",
      "source": "有価証券報告書"
    },
    {
      "date": "1953/1",
      "category": "企業買収",
      "region": "",
      "importance": 1,
      "event": "太陽電設工業（現・住友電設）に資本参加",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1961/1",
      "category": "設備投資",
      "region": "",
      "importance": 1,
      "event": "横浜市に横浜製作所を開設",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1962/1",
      "category": "",
      "region": "",
      "importance": 1,
      "event": "電子線照射イラックスチューブの製造開始、本社を大阪市中央区に移転",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1964/1",
      "category": "",
      "region": "",
      "importance": 1,
      "event": "電子線照射電線の製造開始",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1968/1",
      "category": "",
      "region": "",
      "importance": 2,
      "event": "交通管制システムを事業化",
      "detail": "",
      "significance": "官公庁向けシステム事業の確立。後のITS事業の源流",
      "source": "有価証券報告書"
    },
    {
      "date": "1969/1",
      "category": "",
      "region": "",
      "importance": 2,
      "event": "FPC（フレキシブルプリント回路）の製造開始",
      "detail": "",
      "significance": "エレクトロニクス実装分野への本格進出",
      "source": "有価証券報告書"
    },
    {
      "date": "1970/1",
      "category": "",
      "region": "",
      "importance": 3,
      "event": "化合物半導体の製造開始",
      "detail": "",
      "significance": "後のGaAs・InP・光デバイス事業の起点。非シリコン半導体での独自ポジション形成",
      "source": "有価証券報告書"
    },
    {
      "date": "1974/1",
      "category": "",
      "region": "",
      "importance": 4,
      "event": "光ファイバ・ケーブルの製造開始",
      "detail": "",
      "significance": "国内光通信インフラの担い手としての地位を確立する起点",
      "source": "有価証券報告書"
    },
    {
      "date": "1975/1",
      "category": "組織再編",
      "region": "",
      "importance": 1,
      "event": "営業年度を年1回に変更",
      "detail": "4月1日から翌年3月31日",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1976/1",
      "category": "",
      "region": "",
      "importance": 1,
      "event": "ナイジェリア大規模通信網工事を受注",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1979/1",
      "category": "組織再編",
      "region": "",
      "importance": 1,
      "event": "初の時価発行増資を実施",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1985/1",
      "category": "研究開発",
      "region": "",
      "importance": 2,
      "event": "合成ダイヤモンド単結晶製品の事業化",
      "detail": "",
      "significance": "超硬材料・工具分野での独自技術の事業化",
      "source": "有価証券報告書"
    },
    {
      "date": "1986/1",
      "category": "企業買収",
      "region": "米州",
      "importance": 2,
      "event": "米国にスミトモ エレクトリック ワイヤリング システムズを設立",
      "detail": "",
      "significance": "ワイヤーハーネスの北米現地供給体制の第一歩",
      "source": "有価証券報告書"
    },
    {
      "date": "1994/1",
      "category": "企業買収",
      "region": "米州",
      "importance": 1,
      "event": "米国にスミトモ エレクトリック ライトウェーブを設立",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "1999/1",
      "category": "組織再編",
      "region": "",
      "importance": 2,
      "event": "ブレーキ・ABS事業を住友電工ブレーキシステムズに営業譲渡、高分子機能製品事業を住友電工ファインポリマーとして分社",
      "detail": "",
      "significance": "事業の選択と集中を分社化で推進",
      "source": "有価証券報告書"
    },
    {
      "date": "2001/1",
      "category": "組織再編",
      "region": "",
      "importance": 2,
      "event": "高圧電力用電線事業をジェイ・パワーシステムズに営業譲渡",
      "detail": "日立電線との電力ケーブル統合合弁",
      "significance": "国内電力ケーブル事業の業界再編。日立電線との共同事業体制",
      "source": "有価証券報告書"
    },
    {
      "date": "2002/1",
      "category": "組織再編",
      "region": "",
      "importance": 1,
      "event": "ADSL事業・特殊金属線・巻線事業を会社分割",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "2003/1",
      "category": "組織再編",
      "region": "",
      "importance": 2,
      "event": "建設・電販向け電線を住電日立ケーブルに譲渡、粉末合金・ダイヤ製品を住友電工ハードメタルに分社、執行役員制・事業本部制導入",
      "detail": "",
      "significance": "事業ごと独立採算制への移行と、電線業界再編の継続",
      "source": "有価証券報告書"
    },
    {
      "date": "2006/1",
      "category": "企業買収",
      "region": "欧州",
      "importance": 4,
      "event": "独のワイヤーハーネスメーカー（現・スミトモ エレクトリック ボードネッツェ）を買収",
      "detail": "旧Volkswagen系ハーネスメーカー",
      "significance": "欧州自動車メーカーへのハーネス直接供給体制獲得。世界シェア首位争いの布石",
      "source": "有価証券報告書"
    },
    {
      "date": "2007/1",
      "category": "企業買収",
      "region": "",
      "importance": 3,
      "event": "住友電装を完全子会社化、日新電機を連結子会社化",
      "detail": "",
      "significance": "ワイヤーハーネス世界トップ争いに向けた中核子会社の取り込みと、環境エネルギー事業の強化",
      "source": "有価証券報告書"
    },
    {
      "date": "2009/3",
      "category": "",
      "region": "",
      "importance": 2,
      "event": "リーマンショックで営業利益が急減",
      "detail": "",
      "significance": "自動車・電子部品の需要急減で本業利益が約9割縮小",
      "source": "有価証券報告書",
      "amount": "営業利益2,352億円→235億円"
    },
    {
      "date": "2009/1",
      "category": "組織再編",
      "region": "",
      "importance": 1,
      "event": "光・電子デバイス事業の組織再編により住友電工デバイス・イノベーションを発足",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "2014/1",
      "category": "合弁設立",
      "region": "",
      "importance": 2,
      "event": "ジェイ・パワーシステムズを完全子会社化、住電日立ケーブルを連結子会社化",
      "detail": "国内電力ケーブル事業を単独運営へ",
      "significance": "日立電線との合弁解消。電力ケーブル事業の再単独化",
      "source": "有価証券報告書"
    },
    {
      "date": "2016/6",
      "category": "社長交代",
      "region": "",
      "importance": 2,
      "event": "井上治が社長に就任（松本正義から交代）",
      "detail": "松本は会長へ",
      "significance": "長期在任した松本体制から井上体制への経営移行",
      "source": "有価証券報告書"
    },
    {
      "date": "2019/1",
      "category": "設備投資",
      "region": "",
      "importance": 1,
      "event": "日立市に茨城製作所を開設、テクノアソシエを連結子会社化",
      "detail": "",
      "significance": "",
      "source": "有価証券報告書"
    },
    {
      "date": "2022/1",
      "category": "株式上場",
      "region": "",
      "importance": 2,
      "event": "東証プライム市場へ移行",
      "detail": "",
      "significance": "東証市場区分見直しに伴う移行",
      "source": "有価証券報告書"
    },
    {
      "date": "2023/1",
      "category": "企業買収",
      "region": "",
      "importance": 2,
      "event": "日新電機・テクノアソシエを完全子会社化",
      "detail": "",
      "significance": "上場子会社ガバナンス改革を先取りした親子上場の部分解消",
      "source": "有価証券報告書"
    },
    {
      "date": "2024/1",
      "category": "企業買収",
      "region": "欧州",
      "importance": 3,
      "event": "独の電力ケーブルメーカー、ズートカーベル ゲーエムベーハーを連結子会社化",
      "detail": "",
      "significance": "欧州送電ケーブル市場への足場構築。洋上風力・送電網投資需要の取り込み",
      "source": "有価証券報告書"
    },
    {
      "date": "2025/3",
      "category": "",
      "region": "",
      "importance": 3,
      "event": "通期売上高・営業利益とも過去最高を更新",
      "detail": "生成AI向け光デバイス需要で情報通信が黒字転換",
      "significance": "長期赤字だった情報通信セグメントが生成AI需要で構造転換。自動車偏重からの多極化",
      "source": "IR",
      "amount": "売上46,798億円、営業利益3,207億円、営業利益率6.9%"
    },
    {
      "date": "2025/10",
      "category": "組織再編",
      "region": "",
      "importance": 4,
      "event": "住友電設売却・住友理工完全子会社化を公表",
      "detail": "上場子会社再編によるポートフォリオ入替",
      "significance": "親子上場解消の流れに沿った資本効率改善。売却益を買収原資に充当する入替型再編",
      "source": "IR"
    }
  ]
}