How do I concatenate in a loop based on a condition

[naa]

I want to concatenate several cells into 1 according to condition that there is a break whenever it encounters text "object-group" and then it should start a new concatenate.

Image explains better about what im looking for. I have a LONG list of data in 1 column format, please see image for better explanation of what im after.

I know the concatenate function along with CHAR(10) for line break, but cant figure out how to automate this.

Im looking to fill down formula for column E.

 

[Michael M]

Firstly, your request is doable, but I'd suggest using the XL2BB link to paste real data to the forum rather than and image. Most posters won't bother retyping all of your dat to test it.
See my link for the XL2BB download, then paste the copied data back here.

 

[Michael M]

Try this for starters

Sub MM1()
 Dim r As Long, t As String
 t = ""
For r = Cells(Rows.Count, "B").End(xlUp).Row To 3 Step -1
     If InStr(Cells(r, 2), "object-group") = 0 Then
        t = Cells(r, 2) & Chr(10) & t
        Cells(r, 2).Clear
     Else
         Cells(r, 5) = t
         t = ""
     End If
 Next r
End Sub