diff --git a/client/src/app/shared/dc-validator/utils/applyNumericFormats.ts b/client/src/app/shared/dc-validator/utils/applyNumericFormats.ts
index 5b88803..86a7b48 100644
--- a/client/src/app/shared/dc-validator/utils/applyNumericFormats.ts
+++ b/client/src/app/shared/dc-validator/utils/applyNumericFormats.ts
@@ -7,6 +7,10 @@ import { DcValidation } from '../models/dc-validation.model'
  * Uses Intl.NumberFormat options (HOT 17+) instead of the deprecated numbro
  * `pattern`/`culture`. `maximumFractionDigits: 20` preserves all natural
  * decimals (Intl's default of 3 would round); `locale` replaces `culture`.
+ * `useGrouping: false` keeps raw digits (no thousands separator) - a
+ * separator would leak into anything that pattern-matches the displayed
+ * value (eg HARDREGEX/SOFTREGEX), and grouping can be opted into per-column
+ * with the NUMBER_FORMAT rule.
  *
  * @param rules Cell Validation rules to be updated
  * Those rules are passed in the `columns` property Of handsontable settings.
@@ -14,7 +18,7 @@ import { DcValidation } from '../models/dc-validation.model'
 export const applyNumericFormats = (rules: DcValidation[]): DcValidation[] => {
   for (let rule of rules) {
     if (rule.type === 'numeric') {
-      rule.numericFormat = { useGrouping: true, maximumFractionDigits: 20 }
+      rule.numericFormat = { useGrouping: false, maximumFractionDigits: 20 }
       rule.locale = window.navigator.language
     }
   }