diff --git a/sw/inc/fesh.hxx b/sw/inc/fesh.hxx
index 0c70295e9370..e5c114474425 100644
--- a/sw/inc/fesh.hxx
+++ b/sw/inc/fesh.hxx
@@ -672,7 +672,7 @@ public:
     void SetRowSplit( const SwFormatRowSplit &rSz );
     std::unique_ptr<SwFormatRowSplit> GetRowSplit() const;
 
-    void   SetBoxAlign( sal_uInt16 nOrient );
+    SW_DLLPUBLIC void SetBoxAlign(sal_uInt16 nOrient);
     sal_uInt16 GetBoxAlign() const;         ///< USHRT_MAX if ambiguous.
 
     bool BalanceRowHeight( bool bTstOnly, const bool bOptimize = false );
diff --git a/sw/qa/extras/layout/data/2024-01-19_merged-cells-on-separate-pages-vertical-alignement.odt b/sw/qa/extras/layout/data/2024-01-19_merged-cells-on-separate-pages-vertical-alignement.odt
new file mode 100644
index 000000000000..e316e93fe087
Binary files /dev/null and b/sw/qa/extras/layout/data/2024-01-19_merged-cells-on-separate-pages-vertical-alignement.odt differ
diff --git a/sw/qa/extras/layout/layout5.cxx b/sw/qa/extras/layout/layout5.cxx
index 64d7e33a8b23..eaefdcf69bbf 100644
--- a/sw/qa/extras/layout/layout5.cxx
+++ b/sw/qa/extras/layout/layout5.cxx
@@ -742,6 +742,67 @@ CPPUNIT_TEST_FIXTURE(SwLayoutWriter5, testTdf117245)
     assertXPath(pXmlDoc, "/root/page/body/txt[2]/SwParaPortion/SwLineLayout", 1);
 }
 
+CPPUNIT_TEST_FIXTURE(SwLayoutWriter5, testTdf159029)
+{
+    createSwDoc("2024-01-19_merged-cells-on-separate-pages-vertical-alignement.odt");
+
+    {
+        xmlDocUniquePtr pXmlDoc = parseLayoutDump();
+        assertXPath(pXmlDoc, "/root/page[1]/body/tab[1]/row[1]/cell[2]/infos/bounds", "top",
+                    u"1970");
+        assertXPath(pXmlDoc, "/root/page[1]/body/tab[1]/row[1]/cell[2]/txt[1]/infos/bounds", "top",
+                    u"1970");
+    }
+
+    // set vert orient
+    SwWrtShell* pWrtShell = getSwDocShell()->GetWrtShell();
+    pWrtShell->GotoTable("Table1");
+    pWrtShell->Right(SwCursorSkipMode::Cells, /*bSelect=*/false, 1, /*bBasicCall=*/false);
+    pWrtShell->SetBoxAlign(css::text::VertOrientation::BOTTOM);
+
+    {
+        xmlDocUniquePtr pXmlDoc = parseLayoutDump();
+        assertXPath(pXmlDoc, "/root/page[1]/body/tab[1]/row[1]/cell[2]/infos/bounds", "top",
+                    u"1970");
+        assertXPath(pXmlDoc, "/root/page[1]/body/tab[1]/row[1]/cell[2]/txt[1]/infos/bounds", "top",
+                    u"15494");
+    }
+
+    // delete
+    pWrtShell->SttEndDoc(true);
+    pWrtShell->DelRight();
+
+    {
+        xmlDocUniquePtr pXmlDoc = parseLayoutDump();
+        assertXPath(pXmlDoc, "/root/page[1]/body/tab[1]/row[1]/cell[2]/infos/bounds", "top",
+                    u"1694");
+        // the problem was that this moved to the top of the cell
+        assertXPath(pXmlDoc, "/root/page[1]/body/tab[1]/row[1]/cell[2]/txt[1]/infos/bounds", "top",
+                    u"15494");
+    }
+
+    pWrtShell->Undo();
+
+    {
+        xmlDocUniquePtr pXmlDoc = parseLayoutDump();
+        assertXPath(pXmlDoc, "/root/page[1]/body/tab[1]/row[1]/cell[2]/infos/bounds", "top",
+                    u"1970");
+        // the problem was that this moved to the top of the cell
+        assertXPath(pXmlDoc, "/root/page[1]/body/tab[1]/row[1]/cell[2]/txt[1]/infos/bounds", "top",
+                    u"15494");
+    }
+
+    pWrtShell->Redo();
+
+    {
+        xmlDocUniquePtr pXmlDoc = parseLayoutDump();
+        assertXPath(pXmlDoc, "/root/page[1]/body/tab[1]/row[1]/cell[2]/infos/bounds", "top",
+                    u"1694");
+        assertXPath(pXmlDoc, "/root/page[1]/body/tab[1]/row[1]/cell[2]/txt[1]/infos/bounds", "top",
+                    u"15494");
+    }
+}
+
 CPPUNIT_TEST_FIXTURE(SwLayoutWriter5, testTdf118672)
 {
     createSwDoc("tdf118672.odt");
diff --git a/sw/source/core/layout/tabfrm.cxx b/sw/source/core/layout/tabfrm.cxx
index e61ccacaaafb..f69b94df8a09 100644
--- a/sw/source/core/layout/tabfrm.cxx
+++ b/sw/source/core/layout/tabfrm.cxx
@@ -185,6 +185,22 @@ void SwTabFrame::RegistFlys()
     }
 }
 
+static void InvalidateVertOrientCells(SwRowFrame & rRow)
+{
+    for (SwFrame * pLower{rRow.Lower()}; pLower != nullptr; pLower = pLower->GetNext())
+    {
+        SwCellFrame * pCell{static_cast<SwCellFrame *>(pLower)};
+        if (pCell->GetLayoutRowSpan() != 1)
+        {
+            pCell = const_cast<SwCellFrame *>(&pCell->FindStartEndOfRowSpanCell(true));
+        }
+        if (pCell->GetFormat()->GetVertOrient().GetVertOrient() != text::VertOrientation::NONE)
+        {   // tdf#159029 force repositioning of content in cell because it
+            pCell->InvalidatePrt(); // was disabled by SetRebuildLastLine()
+        }
+    }
+}
+
 static void SwInvalidateAll( SwFrame *pFrame, tools::Long nBottom );
 static void lcl_RecalcRow( SwRowFrame& rRow, tools::Long nBottom );
 static bool lcl_ArrangeLowers( SwLayoutFrame *pLay, tools::Long lYStart, bool bInva );
@@ -865,6 +881,7 @@ static bool lcl_RecalcSplitLine( SwRowFrame& rLastLine, SwRowFrame& rFollowLine,
         // Everything looks fine. Splitting seems to be successful. We invalidate
         // rFollowLine to force a new formatting.
         ::SwInvalidateAll( &rFollowLine, LONG_MAX );
+        InvalidateVertOrientCells(rLastLine);
     }
     else
     {
@@ -2680,6 +2697,7 @@ void SwTabFrame::MakeAll(vcl::RenderContext* pRenderContext)
                                 ::SwInvalidateAll( pLastLine, LONG_MAX );
                                 SetRebuildLastLine( true );
                                 lcl_RecalcRow(*static_cast<SwRowFrame*>(pLastLine), LONG_MAX);
+                                InvalidateVertOrientCells(*static_cast<SwRowFrame *>(pLastLine));
                                 SetRebuildLastLine( false );
                             }