Data　watermark　is　of　the　surmount　importance　for　data　trading.　Most　of　the　data　in　the　current　data　trading　market　is　stored　in　the　form　of　spreadsheets,　yet　there　are　few　watermarking　schemes　specifically　designed　for　tables.　We　propose　a　bitmap-based　watermark　scheme　for　table　data.　Our　approach　involves　converting　the　table　into　a　bitmap　representation　and　utilizing　classical　image　processing　algorithms　to　embed　a　watermark　that　incorporates　error　correction　codes.　The　watermarked　data　is　then　returned　to　its　corresponding　positions　in　the　table.　During　the　table　conversion　process,　we　apply　the　principle　of　minimal　modification　to　minimize　the　impact　of　watermark　embedding　on　the　table　data.　Experimental　evaluations　demonstrate　the　effectiveness　of　the　proposed　scheme　in　preserving　data　integrity　and　accurately　extracting　watermarks.　©　The　Author(s),　under　exclusive　license　to　Springer　Nature　Singapore　Pte　Ltd.　2025.