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SUPPLEMENT TO
PROSPECTUS SUPPLEMENT DATED NOVEMBER 25, 1998
(TO PROSPECTUS DATED NOVEMBER 25, 1998)
PNC MORTGAGE SECURITIES CORP.
DEPOSITOR AND MASTER SERVICER
MORTGAGE PASS-THROUGH CERTIFICATES, SERIES 1998-12
$1,943,884,499
(APPROXIMATE)
The Servicing Fees with respect to the Subgroup II-3 Loans and the Subgroup
III-2 Loans were incorrectly reflected and therefore, certain related
Pass-Through Rates and certain other related calculations were incorrect in the
Prospectus Supplement dated November 25, 1998 to the Prospectus dated November
25, 1998. Accordingly, such Prospectus Supplement is amended as follows:
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<S> <C>
S-5, S-33: The initial Class C-X Notional Amount as of the Closing Date set forth as '$26,640,043' in the
second sentence of footnote (3) on page S-5 and in the last sentence of the second full paragraph on
page S-33 under the caption 'Description of the Certificates -- Distributions of Interest' is
amended to read '$34,881,703.'
S-20, S-21: The weighted average of the Pass-Through Rates for the Subgroup II-3 Loans set forth as
approximately '7.686% per annum' in the paragraph entitled 'The Subgroup II-3 Loans' under the
caption 'Description of the Mortgage Pool -- Loan Group II -- Subgroup II-1 Loans, Subgroup II-2
Loans and Subgroup II-3 Loans' on page S-20 is amended to read '8.186% per annum.' The weighted
average of the Pass-Through Rates for the Subgroup III-2 Loans set forth as approximately '7.202%
per annum' in the paragraph entitled 'The Subgroup III-2 Loans' under the caption 'Description of
the Mortgage Pool -- Loan Group III -- Subgroup III-1 Loans and Subgroup III-2 Loans' on page S-21
is amended to read '7.702% per annum.'
S-56: The weighted average Servicing Fee for the Group II Loans set forth as approximately '0.754%,' the
greatest Servicing Fee for the Group II Loans set forth as '1.640%' and the weighted average
Servicing Fee for the Group III Loans set forth as approximately '0.611%,' in each case under the
caption 'Description of the Certificates -- Servicing Compensation and Payment of Expenses' on page
S-56, are each amended to read '0.686%,' '1.225%' and '0.558%,' respectively.
S-59: In the table entitled 'Groups of Hypothetical Mortgage Loans -- Loan Group II' under the caption
'Yield and Prepayment Considerations -- Prepayment Assumptions' on page S-59, the percent indicated
thereunder in the fourth row of such table as the Pass-Through Rate of '7.6862599329%' is amended to
read '8.1861766731%.'
S-59: In the table entitled 'Groups of Hypothetical Mortgage Loans -- Loan Group III' under the caption
'Yield and Prepayment Considerations -- Prepayment Assumptions' on page S-59, the percent indicated
thereunder in the fifth row of such table as the Pass-Through Rate of '7.2154361196%' is amended to
read '7.7245357633%.' In addition, in the third row of such table, the Subgroup indicated for such
row is amended to read 'III-1 and III-2' and in the fourth row of such table, the Subgroup indicated
for such row is amended to read 'III-1.'
S-63: The table indicating the Pre-Tax Yield to Maturity for the Class C-X Certificates under the caption
'Yield and Prepayment Considerations -- Yield Considerations with Respect to the Interest Only and
Principal Only Certificates' on page S-63 is amended and restated in its entirety to read as
follows:
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PRE-TAX YIELD TO MATURITY OF THE CLASS C-X CERTIFICATES AT AN ASSUMED PURCHASE
PRICE OF 14.000% OF THE INITIAL CLASS C-X NOTIONAL AMOUNT PLUS ACCRUED INTEREST
FROM THE CUT-OFF DATE
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PERCENTAGE OF THE BPA
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0% 50% 100% 150% 200%
- ------- ------- ------- ------- -------
<S> <C> <C> <C> <C>
52.39% 43.51% 34.26% 24.61% 14.48%
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<S> <C>
S-89: The table indicating the Pass-Through Rates for the Group II Loans on page S-89 is amended and
restated in its entirety to read as follows:
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PASS-THROUGH RATES OF THE GROUP II LOANS
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AGGREGATE PRINCIPAL
BALANCE OF THE WEIGHTED AVERAGE
MORTGAGE LOANS WEIGHTED AVERAGE SCHEDULED
RANGE OF AS OF THE MORTGAGE REMAINING TERM
PASS-THROUGH RATES (%) CUT-OFF DATE INTEREST RATES (IN MONTHS)
- ----------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C>
5.501 - 5.750%.............................................. $ 506,000.00 5.925% 360
5.751 - 6.000%.............................................. 2,721,315.91 6.242 360
6.001 - 6.250%.............................................. 6,066,312.23 6.463 360
6.251 - 6.500%.............................................. 9,580,735.92 6.713 360
6.501 - 6.750%.............................................. 22,042,362.70 6.956 358
6.751 - 7.000%.............................................. 311,261,478.05 7.608 358
7.001 - 7.250%.............................................. 144,093,434.44 7.931 359
7.251 - 7.500%.............................................. 111,563,346.51 8.245 359
7.501 - 7.750%.............................................. 70,073,800.53 8.462 357
7.751 - 8.000%.............................................. 41,512,932.02 8.595 353
8.001 - 8.250%.............................................. 32,273,402.52 8.796 358
8.251 - 8.500%.............................................. 36,022,692.33 9.024 358
8.501 - 8.750%.............................................. 18,468,734.67 9.296 357
8.751 - 9.000%.............................................. 6,719,154.15 9.426 356
9.001 - 9.250%.............................................. 1,539,165.14 9.830 358
9.251 - 9.500%.............................................. 835,381.06 10.017 357
9.501 - 9.750%.............................................. 403,367.38 10.057 357
10.751 - 11.000%.............................................. 75,927.32 11.250 358
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Total..................................................... $815,759,542.88 8.004%* 358*
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* Represents a weighted average (by principal balance) of all the Group II
Loans.
As of the Cut-Off Date, the Pass-Through Rates for the Group II Loans
ranged from approximately 5.585% per annum to 10.960% per annum, with a weighted
average of approximately 7.289% per annum.
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<S> <C>
S-91: The table indicating the Pass-Through Rates for the Group III Loans on page S-91 is amended and
restated in its entirety to read as follows:
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<CAPTION>
PASS-THROUGH RATES OF THE GROUP III LOANS
- -------------------------------------------------------------------------------------------------------------------------------
AGGREGATE PRINCIPAL
BALANCE OF THE WEIGHTED AVERAGE WEIGHTED AVERAGE
MORTGAGE LOANS MORTGAGE SCHEDULED
RANGE OF AS OF THE INTEREST REMAINING TERM
PASS-THROUGH RATES (%) CUT-OFF DATE RATES (IN MONTHS)
- -------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C>
5.751 - 6.000%.............................................. $ 215,000.00 6.250% 180
6.001 - 6.250%.............................................. 329,000.00 6.460 180
6.251 - 6.500%.............................................. 1,232,938.99 6.698 179
6.501 - 6.750%.............................................. 4,823,585.58 6.945 179
6.751 - 7.000%.............................................. 21,900,247.63 7.533 179
7.001 - 7.250%.............................................. 7,201,751.84 7.907 179
7.251 - 7.500%.............................................. 7,992,724.22 8.064 178
7.501 - 7.750%.............................................. 4,392,203.10 8.338 177
7.751 - 8.000%.............................................. 2,700,828.64 8.479 170
8.001 - 8.250%.............................................. 990,303.33 8.787 177
8.251 - 8.500%.............................................. 642,175.21 9.061 179
8.501 - 8.750%.............................................. 271,319.33 9.601 179
9.751 - 10.000%.............................................. 37,831.01 10.990 174
10.001 - 10.250%.............................................. 101,266.15 10.500 179
--
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Total...................................................... $ 52,831,175.03 7.755%* 178*
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* Represents a weighted average (by principal balance) of all the Group III
Loans.
As of the Cut-Off Date, the Pass-Through Rates for the Group III Loans
ranged from approximately 5.950% per annum to 10.210% per annum, with a weighted
average of approximately 7.171% per annum.
In addition, the Prospectus Supplement dated November 25, 1998 to the
Prospectus dated November 25, 1998 is further amended as follows:
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<S> <C>
S-44: The definition of the 'Class IV-A-3 Percentage' set forth in the first sentence of the third full
paragraph on page S-44 is amended to read as follows:
'The `CLASS IV-A-3 PERCENTAGE' for any Distribution Date will equal the lesser of (a) 100% and (b)
the Class IV-A-3 Principal Balance divided by the aggregate Stated Principal Balance of the Group IV
Loans (less the Class IV-P Principal Balance), in each case immediately prior to the Distribution
Date.'
S-53: Clause (a) under subparagraph (1) of the definition of the 'Available Distribution Amount' set forth
on page S-53 is amended to read as follows:
'(a) all scheduled payments of principal and interest collected but due on or subsequent to such
Distribution Date;'
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The date of this Supplement is December 10, 1998.
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