Waterfall Forensics.

Prime fixed-rate RMBS

Wells Fargo Mortgage Backed Securities 2007-12

424B5 filed 2007-08-27, acc 0001193125-07-189590

machine-encoded from the prospectus by the extraction pipeline and tied out over 4 periods (2007-09-25 to 2007-12-26); not yet expert-verified

Backtested periods

4

2007-09-25 to 2007-12-26

Comparison points within $1

100.0%

192 points

Max principal delta

$0.02

interest $0.01 · balance $0.02

What the encoder found in the filings

  • dropped A-1, A-2, A-3, A-4, A-5, A-6, A-15, A-16, A-17, A-18, A-19, A-20, A-21: never reported by the trustee, so not part of the deal as issued
  • A-PO: draft face 719,718.00 -> reported 719,718.65 (pinned from the remittance Original Balance)
  • B-6: draft face 564,115.00 -> reported 564,115.46 (pinned from the remittance Original Balance)
  • group 1 has 10 senior classes (A-7, A-8, A-9, A-10, A-11, A-12, A-13, A-14, A-PO, A-R); assumed pro rata, but the contract may pay them as components — check the tie-out
  • exchangeable certificates left out of the tie-out (their rows duplicate the underlying classes): A-1, A-15, A-16, A-17, A-18, A-19, A-2, A-20, A-21, A-3, A-4, A-5, A-6
  • window starts at deal month 1 (2007-09-25); earlier reports are not in the machine-readable run

Capital structure · original faces

A-7
$71,000,000.00
A-8
$1,970,000.00
A-9
$237,586,000.00
A-10
$6,593,000.00
A-11
$19,172,000.00
A-12
$532,000.00
A-13
$27,242,000.00
A-14
$756,000.00
A-PO
$719,718.65
A-R
$100.00
B-1
$5,448,000.00
B-2
$1,879,000.00
B-3
$939,000.00
B-4
$939,000.00
B-5
$376,000.00
B-6
$564,115.46

viridian = senior (per-pool) · burgundy = cross-collateralized subordinates

Worst remaining deltas · computed vs reported

interest

2007-11-26A-9+0.01
2007-10-25B-6-0.01
2007-11-26B-6+0.01
2007-12-26B-2-0.01
2007-10-25A-7+0.01

principal

2007-09-25A-9+0.02
2007-09-25A-PO-0.01
2007-09-25B-6+0.01
2007-10-25A-PO-0.01
2007-10-25B-6-0.01

ending balance

2007-12-26A-9-0.02
2007-10-25A-9-0.02
2007-11-26A-9-0.02
2007-12-26A-PO+0.02
2007-09-25A-9-0.02