<PAGE>   1

                                   FORM 10-QSB

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

(Mark One)

              [X] QUARTERLY REPORT UNDER SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                For the quarterly period ended: December 31, 1998

          [ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                             SECURITIES ACT OF 1934

          For the transition period from _____________ to _____________

                         Commission File Number 0-13022

                                INTELLICORP, INC.
        (Exact name of small business issuer as specified in its charter)

<TABLE>
<S>                                                          <C>
           DELAWARE                                              94-2756073
(State or other jurisdiction of                               (I.R.S. Employer
incorporation or organization)                               Identification No.)
</TABLE>

                            1975 EL CAMINO REAL WEST
                      MOUNTAIN VIEW, CALIFORNIA 94040-2216
                    (Address of principal executive offices)
                                   (Zip Code)

                                 (650) 965-5500
                (Issuer's telephone number, including area code)


Check whether the issuer (1) filed all reports required to be filed by section
13 or 15(d) of the Securities Exchange Act during the past 12 months (or for
such shorter period that the registrant was required to file such reports), and
(2) has been subject to such filing requirements for the past 90 days.

                               YES [X]     NO [ ]

                      APPLICABLE ONLY TO CORPORATE ISSUERS:

Indicate the number of shares outstanding of each of the issuer's classes of
common equity, as of the latest practicable date.

<TABLE>
<CAPTION>
                                             Outstanding as of
           Class                             January 31, 1999
           ---------------------             -----------------
<S>                                          <C>
           Common stock,
           $.001 par value                   15,218,869 shares
</TABLE>

                     This document is comprised of 13 pages.

<PAGE>   2

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
PART I.  FINANCIAL INFORMATION                                             Page
                                                                           ----
<S>              <C>                                                       <C>
     Item 1.     Financial Statements
                 Condensed Consolidated Balance Sheets......................  3
                 Condensed Consolidated Statements of Operations............  4
                 Condensed Consolidated Statements of Cash Flows............  5
                 Notes to Condensed Consolidated Financial Statements.......  6

     Item 2.     Management's Discussion and Analysis of
                 Financial Condition and Results of Operations...........  7-10


PART II. OTHER INFORMATION

     Item 6.     Exhibits and Reports on Form 8-K..........................  11

SIGNATURE..................................................................  12
</TABLE>


                                       2

<PAGE>   3

PART I.  FINANCIAL INFORMATION

ITEM 1.  FINANCIAL STATEMENTS

INTELLICORP, INC.
CONDENSED CONSOLIDATED BALANCE SHEETS

<TABLE>
<CAPTION>

                                                     December 31,      June 30,
(In thousands)                                          1998           1998(1)
                                                     ------------      --------
                                                            (unaudited)
<S>                                                   <C>              <C>     
Assets
Current assets:
Cash and cash equivalents                             $  2,795         $  4,714
Short-term investments                                   1,472
Accounts receivable, net                                 6,312            7,157
Other current assets                                       433              327
                                                      --------         --------
     Total current assets                                9,540           13,670

Property and equipment, net                              1,220            1,101
Purchased intangibles, net                               2,934            3,431
Other assets                                               178              252
                                                      --------         --------

                                                      $ 13,872         $ 18,454
                                                      ========         ========

Liabilities and Stockholders' Equity
Current liabilities:
Accounts payable                                      $  1,297         $  1,410
Accrued compensation                                     1,205            1,321
Other current liabilities                                1,749            1,589
Deferred revenues                                        1,868            2,377
                                                      --------         --------
     Total current liabilities                           6,119            6,697

Convertible notes                                        1,600            1,600

Stockholders' equity:
Preferred stock                                              1                1
Common stock                                                15               15
Additional paid - in capital                            58,522           58,487
Accumulated deficit                                    (52,385)         (48,346)
                                                      --------         --------
     Total stockholders' equity                          6,153           10,157
                                                      --------         --------

                                                      $ 13,872         $ 18,454
                                                      ========         ========
</TABLE>

(1)  The consolidated balance sheet at June 30, 1998, has been derived from the
     audited consolidated financial statements at that date but does not include
     all of the information and footnotes required by generally accepted
     accounting principles for complete financial statements.

See notes to condensed consolidated financial statements.


                                       3

<PAGE>   4

INTELLICORP, INC.
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

<TABLE>
<CAPTION>
                                             Three months ended              Six months ended
                                                 December 31,                  December 31,
(In thousands, except                       -----------------------       -----------------------
per share amounts)                            1998           1997           1998           1997
                                            --------       --------       --------       --------
                                                (unaudited)                      (unaudited)
<S>                                         <C>            <C>            <C>            <C>     
Revenues:
     Software                               $  1,581       $  3,459       $  2,859       $  6,359
     Contract services                         3,231          1,528          6,296          2,978
     Other services                              838            529          1,633            959
                                            --------       --------       --------       --------
     Total revenues                            5,650          5,516         10,788         10,296
                                            --------       --------       --------       --------

Costs and expenses:
     Cost of revenues:
       Software                                  344            210            613            472
       Contract services                       2,335            724          4,431          1,404
       Other services                            173            208            368            385
     Research and development                  1,657          1,337          3,223          2,409
     Marketing, general, and
       administrative                          3,198          2,384          5,951          4,535
                                            --------       --------       --------       --------
     Total costs and expenses                  7,707          4,863         14,586          9,205
                                            --------       --------       --------       --------

Income (loss) from operations                 (2,057)           653         (3,798)         1,091

Other income (expense), net                      (18)            67             49             91
                                            --------       --------       --------       --------

Income (loss) before provision
     for income taxes                         (2,075)           720         (3,749)         1,182

Provision for income taxes                      --               69             20            106
                                            --------       --------       --------       --------

Net income (loss)                           $ (2,075)      $    651       $ (3,769)      $  1,076
                                            ========       ========       ========       ========

Series A and Series B Preferred
     stock dividends                            (135)          (160)          (270)          (322)
                                            --------       --------       --------       --------

Income (loss) available to
     Common shareholders                    $ (2,210)      $    491       $ (4,039)      $    754
                                            ========       ========       ========       ========

Net income (loss) per share - basic         $  (0.15)      $   0.04       $  (0.27)      $   0.06
                                            ========       ========       ========       ========

Net income (loss) per share - diluted       $  (0.15)      $   0.03       $  (0.27)      $   0.05
                                            ========       ========       ========       ========

Weighted average common
      shares outstanding - basic              15,215         13,471         15,194         13,258
                                            ========       ========       ========       ========

Weighted average common
     shares outstanding - assuming
     dilution                                 15,215         15,143         15,194         15,023
                                            ========       ========       ========       ========
</TABLE>

See notes to condensed consolidated financial statements.


                                       4

<PAGE>   5

INTELLICORP, INC.
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

<TABLE>
<CAPTION>
                                                                 Six months ended
                                                                    December 31,
Increase (decrease) in cash and                                ---------------------  
cash equivalents (in thousands)                                  1998          1997
                                                               -------       -------
                                                                    (unaudited)
<S>                                                            <C>           <C>    
Cash flows from operating activities:
     Net income (loss)                                         $(3,769)      $ 1,076
     Adjustments to reconcile net loss to net
         cash used in operating activities:
     Depreciation and amortization                                 825           258
     Issuance of common stock in lieu of interest payment          --             90
     Changes in assets and liabilities:
         Accounts receivable                                       845        (1,141)
         Other current assets                                     (106)         (131)
         Other assets                                               74            85
         Accounts payable                                         (113)          300
         Accrued compensation                                     (116)          146
         Other current liabilities                                 160           402
         Deferred revenues                                        (509)          446
                                                               -------       -------
     Net cash provided by (used in) operating activities        (2,709)        1,531
                                                               -------       -------

Cash flows from investing activities:
     Property and equipment purchases                             (447)         (389)
     Purchase of short-term investments                            --         (3,620)
     Maturities of short-term investments                        1,472         3,515
                                                               -------       -------
Net cash provided by (used in) investing activities              1,025          (494)
                                                               -------       -------

Cash flows from financing activities:
     Payment of dividends                                         (270)         --
     Cash received from exercise of warrants                       --           712
     Cash received from sale of stock                              35           133
                                                               -------       -------
Net cash provided by (used in) financing activities               (235)          845
                                                               -------       -------

Increase (decrease) in cash and cash equivalents                (1,919)        1,882
Cash and cash equivalents, beginning of period                   4,714         4,363
                                                               -------       -------

Cash and cash equivalents, end of period                       $ 2,795       $ 6,245
                                                               =======       =======
</TABLE>

See notes to condensed consolidated financial statements.


                                       5

<PAGE>   6

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

1.   BASIS OF PRESENTATION. The accompanying condensed consolidated financial
statements should be read in conjunction with the Company's consolidated
financial statements for the fiscal year ended June 30, 1998, included in the
Company's Annual Report on Form 10-KSB filed with the Securities and Exchange
Commission. In the opinion of management, the interim statements reflect all
adjustments (consisting of normal recurring entries) which are necessary for a
fair presentation of the results of the interim periods presented. The interim
results are not necessarily indicative of the results for the full year.

RECLASSIFICATIONS. The Company has reclassified certain prior year balances to
conform with current year presentation.

2.   SIGNIFICANT CUSTOMERS AND EXPORT SALES. A related party accounted for 24%
($1,373,000) and 27% (2,878,000), respectively, of the total revenues for the
three and six month periods ended December 31, 1998 and 20% ($1,120,000) and 24%
($2,424,000), respectively, of the revenues for the three and six month periods
ended December 31, 1997. One other related party accounted for 11% ($604,000)
and 10% ($1,107,000), respectively, of the total revenues for the three and six
month periods ended December 31, 1998. A commercial customer accounted for 15%
($838,000) of the total revenues for the three month period ended December 31,
1997.

3.   INCOME TAXES. The Company's provision for income taxes of $20,000 for the
three and six months ended December 31, 1998 is attributable to income taxes,
primarily state and local. The provision for income taxes of $69,000 and
$106,000, respectively, for the three and six months ended December 31, 1997 is
attributable to income taxes and foreign withholding taxes.

4.   NEW ACCOUNTING STANDARD. As of July 1, 1998, the Company adopted Statement
130 (SFAS 130), "Reporting Comprehensive Income." SFAS 130 establishes new rules
for the reporting and display of comprehensive income and its components;
however, the adoption of SFAS 130 had no impact on the Company's net loss or
stockholders' equity. SFAS 130 requires unrealized gains or losses on the
Company's available for-sale securities, which prior to adoption were reported
separately in stockholders' equity, to be included in other comprehensive
income.

5.   EARNINGS PER SHARE. In 1997, The Financial Accounting Standards Board
issued Statement of Financial Accounting Standards No. 128, Earnings Per Share.
Statement 128 replaced primary and fully diluted earnings per share under APB 15
with basic and diluted earnings per share. Unlike primary earnings per share,
basic earnings per share excludes any dilutive effects of options, warrants, and
convertible securities. Diluted earnings per share is very similar to the
previously reported fully diluted earnings per share. All earnings per share
amounts for all periods have been presented, and where necessary, restated to
conform to the Statement 128 requirements. The following table sets forth the
computation of basic and diluted earnings (loss) per share.

During the quarter and six months ended December 31, 1998 and 1997, total
comprehensive income approximated net income or net loss for each of these 
respective years.

<TABLE>
<CAPTION>
(in thousands, except per share amounts)
                                                 -----------------------------------------------------
                                                   Three Months Ended            Six Months Ended
                                                       December 31,                 December 31,
                                                 -----------------------       -----------------------
                                                   1998            1997          1998           1997
                                                 --------       --------       --------       --------
<S>                                              <C>            <C>            <C>            <C>     
Numerator:
     Net income/(loss)                           $ (2,075)      $    651       $ (3,769)      $  1,076
     Preferred stock dividends                       (135)          (160)          (270)          (322)
                                                 --------       --------       --------       --------
     Income/(loss) available to common
       shareholders                                (2,210)           491         (4,039)           754 
                                                 ========       ========       ========       ========

Denominator:
Average shares outstanding-basic                   15,215         13,471         15,194         13,258
Effect of dilutive securities:
Employee and director stock options                                1,570                         1,589
Warrants                                                             102                           176
                                                 --------       --------       --------       --------
Average shares outstanding-
      assuming dilution                            15,215         15,143         15,194         15,023
                                                 ========       ========       ========       ========

Earnings (loss) per share-basic                  $  (0.15)      $   0.04       $  (0.27)      $   0.06
                                                 ========       ========       ========       ========

Earnings (loss) per share-assuming dilution      $  (0.15)      $   0.03       $  (0.27)      $   0.05
                                                 ========       ========       ========       ========
</TABLE>

Common stock equivalents excluded from the computation of diluted shares
outstanding at December 31, 1998 include 2,961,000 stock options, convertible
preferred stock (435,000 shares of series A and 5,000 shares of series B)
convertible notes (convertible to 1,032,000 shares of common stock), and
warrants to purchase 720,000 shares of common stock as their inclusion would be
ant-dilutive.


                                       6

<PAGE>   7

ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
        OF OPERATIONS

Other than statements of historical fact, the statements made in this report on
Form 10-QSB are forward-looking statements that involve risks and uncertainties.
The Company's actual results may differ materially from the results discussed in
the forward-looking statements. Factors that might cause such a difference
include, but are not limited to, those discussed in "Results of Operations" and
"Liquidity and Capital Resources" below and in "Risk Factors" in the Company's
Annual Report on Form 10-KSB for the fiscal year ended June 30, 1998.

In particular, it is important to note that achievement of revenue goals is
affected by numerous factors beyond the Company's control, including
competitors' product introductions, market price competition and market
acceptance of the Company's products. Historical results of the Company may not
be indicative of future operating results.


RESULTS OF OPERATIONS

The Company's total revenue is derived from three sources: contract services,
software licenses, and other services, which is primarily comprised of product
support revenue. In prior periods training revenue was included in other
services. The change in the classification of training revenue from other
services to contract services was made to more accurately reflect the manner in
which the business is managed internally. Certain prior period balances have
been restated to reflect this reclassification.

Total revenues were $5,650,000 and $10,788,000, respectively, for the three and
six months ended December 31, 1998, compared to $5,516,000 and $10,296,000,
respectively, for the same periods in the prior year. This represents a 2% and
5% increase, respectively, for the three and six month periods ended December
31, 1998 compared to the same prior year periods.

The geographic breakdown of revenue is as follows:

<TABLE>
<CAPTION>
                                Three months ended          %            Six months ended            %
                                   December 31,           Change            December 31,           Change
                               --------------------      -------        --------------------      -------
(In thousands)                   1998         1997                        1998         1997
                               -------      -------      -------        -------      -------      -------
<S>                            <C>          <C>              <C>        <C>          <C>               <C> 
North America                  $ 3,778      $ 4,347          (13)%      $ 7,376      $ 8,006           (8)%
Europe                           1,728          964           79%         3,095        1,759           76%
Pacific Rim/Latin America          144          205          (28)%          317          531          (40%)
                               -------      -------      -------        -------      -------      -------
     Total revenue             $ 5,650      $ 5,516            2%       $10,788      $10,296            5%
</TABLE>

The geographic revenue as a percentage of revenue is as follows:

<TABLE>
<CAPTION>
                                         Three months ended             Six months ended
                                             December 31,                  December 31,
                                         ------------------            -------------------
                                         1998          1997            1998           1997
                                         ----          ----            ----           ----
<S>                                      <C>           <C>             <C>            <C>
North America                             67%           79%             68%            78%
Europe                                    30%           17%             29%            17%
Pacific/Latin America                      3%            4%              3%             5%
                                        -----         -----           -----           ----
     Total                               100%          100%            100%           100%
</TABLE>

Software revenues for the three and six month periods ended December 31, 1998,
respectively, decreased 54% and 55% compared to the same periods in the prior
year. Both the three and six month decreases are primarily attributable to
transitions in the Company's sales and marketing organization, which begun in
the first quarter of this fiscal year, and uncertainties created by a shift in
SAP's business process modeling direction. In the second quarter of fiscal 1999
the Company continued to take actions to address these issues. A new executive
vice 


                                       7

<PAGE>   8

president of worldwide sales was hired in the second quarter, several new field
sales managers were hired to replace existing sales managers, the sales and
marketing organization was put through a focused training curriculum, and the
Company has re-focused and increased its lead generation efforts. In addition,
the Company is further integrating its LiveModel product with SAP's ASAP
implementation methodology, and launched a new business process management
program called LiveCompass, which is sold to the existing SAP R/3 install base.
Intellicorp also launched a new application integration product called
LiveTransfer which, combined with LiveInterface, provides a robust end-to-end
solution for transferring data between SAP R/3 and other software applications.

Contract services revenues, which includes training revenues, for the three and
six month periods ended December 31, 1998, increased 111% compared to the same
periods a year ago. The increases are due to growth in most services, including
custom development work, LiveModel consulting, LiveInterface consulting, and
configure to order consulting.

Other services revenue increased 58% and 70% during the three and six months
ended December 31, 1998, compared to the same periods a year ago. The increase
is primarily due to product support revenues related to LiveInterface and
LiveModel.

Gross margin, as a percentage of total revenues for the three and six months
ended December 31, 1998, was 50% compared to 79% and 78% in the same periods in
the prior year. Software margins were 78% and 79% for the three and six months
ended December 31, 1998, compared to 94% and 93% for same prior year periods.
The decrease in software margins is due to decreased sales volume on a
relatively fixed cost base, as well as amortization expense incurred in fiscal
1999 related to acquired technology. Contract services margins were 28% and 30%
for the three and six months ended December 31, 1998, compared to 53% in each of
the same periods in the prior year. The decrease in contract services margins
compared to the prior year quarters is due to two factors. First, the Company's
shortfall in software revenue resulted in lower utilization rates in the
consulting business as the consulting business is directly affected by the
Company's software license sales. Second, the Company had infrastructure costs
in the first two quarters of fiscal 1999 associated with the LiveInterface
consulting business acquired in the third quarter of fiscal 1998 that it did not
have in the first two quarters of fiscal 1998. Other services margins were 79%
and 77% for the three and six month periods ended December 31, 1998 compared to
61% and 60% for the same prior year periods. The increases in the fiscal 1999
quarters over the prior year quarters is primarily due to increased support
revenues on a relatively fixed cost base.

Research and development (R&D) expenses increased $320,000 (24%) and $814,000
(34%) during the three and six months ended December 31, 1998 from the same
prior year periods. The increases are due primarily to increased headcount and
higher labor costs related to continuing development on LiveModel: SAP R/3 as
well as development costs associated with LiveInterface. R&D expenses, as a
percentage of total revenues for the three and six months ended December 31,
1998 were 29% and 30% compared to 24% and 23% in the same prior year periods.

Marketing, general and administrative expenses increased $814,000 (34%) and
$1,416,000 (31%), respectively, during the three and six months ended December
31, 1998, compared to the same prior year periods. The increases are due to
several factors, including, labor costs, contractor and consultant fees,
recruiting costs, trade show expenses, expenses related to the opening of a
French office, provision for certain customer allowances, sales training
expense, and expenses related to the LiveInterface operations in Philadelphia.
In total, marketing, general and administrative expenses were 57% and 55% of
revenues for the three and six months ended December 31, 1998, compared to 43%
and 44% of revenues for the same periods last year.

Other income and expense, net, which includes interest income and expense, for
the three and six months ended December 31, 1998 decreased $85,000 and $42,000
compared with the same periods in the prior year primarily due to decreased
interest income due to lower short term investment balances.

The provision for income taxes of $20,000 for the six months ended December 31,
1998 is due to income taxes (primarily state and local). This compares to
$106,000 related to income and foreign withholding taxes in the same prior year
period.


                                       8

<PAGE>   9

LIQUIDITY AND CAPITAL RESOURCES

At December 31, 1998, cash, cash equivalents and short-term investments were
$2,795,000 compared to $8,379,000 at December 31, 1997.

The Company had a net loss of $3,769,000 for the first six months of fiscal 1999
compared to a net income of $1,076,000 for the first six months of fiscal 1998.
Cash used in operations was $2,709,000 during the first six months of fiscal
1999, compared to $1,531,000 provided by operations in the same period in the
prior year. The increase in cash used in operations is primarily due to the net
loss incurred in the current year period versus the net income in the prior year
period.

Cash provided by investing activities was $1,025,000 in the first six months of
fiscal 1999 compared to $494,000 used in investing activities in the first six
months of fiscal 1998. The increase in cash provided by investing activities is
due primarily to the maturity of short term investments in the first six months
of fiscal 1999 whereas the maturity of short term investments in the same prior
year period is offset with additional purchases of short term investments in 
that period.

Cash used in financing activities was $235,000 in the current year period versus
$845,000 provided by financing activities in the prior year quarter. In the
current year period the Company paid cash dividends of $270,000 on the Company's
outstanding preferred stock whereas in the prior year period the Company issued
common stock in lieu of cash dividends on the Company's outstanding preferred
stock. Additionally, the Company received $712,000 from warrants exercised in
the prior year period.

The Company believes its cash, cash equivalents at December 31, 1998 along with
expected cash generated from operations will be adequate to fund its operations
during fiscal 1999. As an additional contingent measure, the company is
exploring various financing alternatives, both bank line and equity, to use if,
when, and as needed. There can be no assurance, however, that the Company will
be able to raise additional capital on favorable terms, if at all. If revenues
for the remainder of fiscal 1999 do not meet management's expectations, and
additional financings are not available, management has the ability and may
further reduce certain expenditures to lower the Company's cost base, if
required.


YEAR 2000 ISSUE

The Company has conducted a comprehensive review of its information technology
and non-information technology systems to identify the systems that could be
affected by the year 2000 Issue. The year 2000 issue is the result of computer
programs being written using two digits rather than four to define applicable
year. Any of the Company's programs that have time-sensitive software or micro
controllers may recognize a date using "00" as the year 1900 rather than the
year 2000. This could result in a major system failure or miscalculations. The
Company believes any modifications deemed necessary will be made on a timely
basis and does not believe that the cost of such modifications will have a
material effect on the Company's operating results. Additionally, the Company is
in the process of evaluating the need for contingency plans with respect to year
2000 requirements. The necessity of any contingency plan must be evaluated on a
case by case basis and will vary considerably in nature depending on the year
2000 issue it may need to address. The Company's expectations as to the extent
and timeliness of modifications required in order to achieve Year 2000
compliance is a forward-looking statement subject to risks and uncertainties.
Actual results may vary materially as a result of a number of factors,
including, among others, those described in this paragraph and the paragraph
below. There can be no assurance however, that the Company will be able to
successfully modify on a timely basis such products, services and systems to
comply with year 2000 requirements, which failure could have a material adverse
effect on the Company's operating results.


                                       9

<PAGE>   10

Based on the Company's assessment to date, all newly introduced products and
services of the Company are year 2000 compliant, however, some of the Company's
customers are running product versions that are not year 2000 compliant. The
Company has been encouraging such customers to migrate to current product
versions. In addition, the Company faces risks to the extent that suppliers of
products, services and systems purchased by the Company and others with whom the
Company transacts business on a worldwide basis do not have business systems or
products that comply with the year 2000 requirements. To the extent that
IntelliCorp is not able to test technology provided by third party hardware or
software vendors, IntelliCorp is in the process of obtaining assurances from
such vendors that their systems are year 2000 compliant. In the event that any
third parties cannot provide the Company with products, services or systems that
meet the year 2000 requirements in a timely manner, the Company's operating
results could be materially adversely affected. Although the Company believes
that the cost of year 2000 modifications for internal use software and systems
and the Company's products is not material, there can be no assurance that
various factors relating to year 2000 compliance issues, including litigation,
will not have a material adverse effect on the Company's business, operating
results or financial position.


PURCHASED INTANGIBLE ASSETS

On January 23, 1998, the Company entered into an asset purchase agreement with
ICS Deloitte Management LLC, an affiliate of Deloitte & Touche, ("D&T") to
purchase the rights to the Universal Portable Interface ("UPI") technology. This
technology consisted of the intellectual and proprietary property comprised of
UPI and included all related copyrights, processes, designs, formulas,
inventions, trade secrets, know-how, technology, methodologies, principles of
operations flow charts, schematics, codes and databases.

At the time of acquisition, revenues for developed and core technology were
estimated for the remainder of fiscal 1998 through fiscal 2004. The Company
anticipated that sales of the acquired developed product would decline
significantly during fiscal 1999. While Q1 and Q2 fiscal 1999 revenues related
to the acquired developed product were lower than initial estimates, Q3 and Q4
fiscal 1998 revenues were higher than initial estimates. Revenues from the
acquisition date through the end of the first half of fiscal 1999, related to
the developed and core technology, have been lower, somewhat, than initial
expectations. Management believes that the cause of the revenue shortfall in the
first half of fiscal 1999 is due to a combination of internal sales and
marketing transition issues and increased competitive pressures. As of the end
of the second quarter of fiscal 1999, the Company believes that total revenues
over the life of the product will not differ to such an extent as to require a
devaluation of the current carrying value of the intangible products. As of the
end of the second quarter of fiscal 1999 no change has occurred with respect to
management's expectation that revenues are anticipated to shift to the new
product solution which is expected to be introduced into the market in fiscal
year 1999. It should be noted that while revenues allocated to the developed and
in-process technologies are expected to individually phase down over time
(consistent with normal software product life cycles), the composite revenue
attributed to all applications integration products and technologies (including
future follow-on technologies) is planned to continue growing in the foreseeable
future.

At the time of acquisition, the Company estimated that an aggregate of
approximately $2.0 million of research and development spending is anticipated
over an approximately one year development period from the acquisition date in
order to develop the acquired in-process research and development into a viable
product offering. While the Company expects the completion of this viable
product offering to be delayed a few months, compared to the original estimate,
the total cost needed to complete development is not expected to differ
materially from initial estimates.


                                       10

<PAGE>   11

PART II.  OTHER INFORMATION

ITEM 6.   EXHIBITS AND REPORTS ON FORM 8-K

     a)   Exhibits

          27 - Financial Data Schedule.

     c)   Reports on Form 8-K

          No reports have been filed for the quarter ended December 31, 1998.


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                                    SIGNATURE


Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                         INTELLICORP, INC.


                                         /s/ Kenneth A. Czaja
                                         ----------------------
                                         Kenneth A. Czaja
                                         Chief Financial Officer


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<PAGE>   13

                                INDEX TO EXHIBITS

<TABLE>
<CAPTION>
Exhibit                                                           Sequentially
  No.                       Description                           Numbered Page
-------               -----------------------                     -------------
<S>                   <C>                                              <C>
  27                  Financial Data Schedule
</TABLE>


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