<PAGE>

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                            -------------------------

                                   Form 10-Q/A

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


For Quarter Ended: January 31, 1998             Commission File Number 0-26714
                   ----------------                                    -------


                                 ADE CORPORATION
             (Exact name of registrant as specified in its charter)


         Massachusetts                                         04-2441829
         -------------                                         -----------
(State or other jurisdiction of                             (I.R.S. Employer
 incorporation or organization)                          Identification Number)


                  80 Wilson Way, Westwood, Massachusetts 02090
                  --------------------------------------------
          (Address of principal executive offices, including area code)


                                 (781) 467-3500
                                 --------------
              (Registrant's telephone number, including area code)


     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 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 ______

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


Common Stock, par value $.01 per share                   13,137,412 shares
----------------------------------------           ----------------------------
                 Class                             Outstanding at July 22, 1998




<PAGE>

                                 ADE CORPORATION

                                      INDEX
<TABLE>
<CAPTION>
                                                                                                 Page
                                                                                                 ----
<S>                                                                                              <C>
Part I.  -  Financial Information

     Item 1.    Condensed Consolidated Financial Statements (unaudited)

                  Condensed Consolidated Balance Sheet--
                      January 31, 1998 and April 30, 1997 .......................................  3

                  Condensed Consolidated Statement of Income--
                      Three and Nine Months Ended January 31, 1998 and 1997 .....................  4

                  Condensed Consolidated Statement of Cash Flows--
                      Nine Months Ended January 31, 1998 and 1997 ...............................  5

                  Notes to Unaudited Condensed Consolidated Financial Statements ................  6

     Item 2.    Management's Discussion and Analysis of Financial Condition
                 and Results of Operations ...................................................... 11

Part II.  -  Other Information .................................................................. 16

Signatures ...................................................................................... 17

Exhibit Index ................................................................................... 18

</TABLE>



                                       2
<PAGE>

                                 ADE CORPORATION
                      CONDENSED CONSOLIDATED BALANCE SHEET
                                 (in thousands)
<TABLE>
<CAPTION>

                                                            January 31,   April 30,
                                                              1998*          1997
                                                             ---------     --------
                                                            (unaudited)
<S>                                                          <C>           <C>  

Assets
Current assets:

  Cash and cash equivalents .............................    $  69,296     $ 19,374
  Accounts receivable, net ..............................       23,947       20,331
  Inventories ...........................................       28,546       22,160
  Prepaid expenses and other current assets .............        1,533          310
  Deferred income taxes .................................        6,584        5,348
                                                             ---------     --------
        Total current assets ............................      129,906       67,523

Fixed assets, net .......................................       22,315       15,735
Deferred income taxes ...................................        2,423          234
Investments .............................................        3,604        3,162
Intangible assets, net ..................................        5,277        1,500
Restricted cash .........................................        3,914           --
Other assets ............................................          312          263
                                                             ---------     --------

                                                             $ 167,751     $ 88,417
                                                             ---------     --------
                                                             ---------     --------

Liabilities and Stockholders' equity 
Current liabilities:
  Current portion of long-term debt .....................    $     447     $    899
  Accounts payable ......................................        4,994        5,535
  Accrued expenses ......................................       10,971       10,744
  Deferred income on sales to affiliate .................        2,547        2,661
  Income taxes payable ..................................           --        1,915
                                                             ---------     --------
      Total current liabilities .........................       18,959       21,754
                                                             ---------     --------

Long-term debt ..........................................        8,707        5,091

Excess of net assets acquired over cost .................          ---          184
                                                             ---------     --------

Stockholders' equity:
  Common stock ..........................................          111           86
  Capital in excess of par value ........................       98,987       28,660
  Retained earnings .....................................       41,145       32,846
                                                             ---------     --------

                                                               140,243       61,592

  Deferred compensation .................................         (158)        (204)
                                                             ---------     --------

                                                               140,085       61,388
                                                             ---------     --------

                                                             $ 167,751     $ 88,417
                                                             ---------     --------
                                                             ---------     --------

</TABLE>

                             *Restated--see note 9.

    The accompanying notes are an integral part of these unaudited condensed
                       consolidated financial statements.

                                       3
<PAGE>

                                 ADE CORPORATION

                   CONDENSED CONSOLIDATED STATEMENT OF INCOME
               (in thousands, except per share amounts; unaudited)


<TABLE>
<CAPTION>

                                                             Three months ended    Nine months ended
                                                                 January 31,          January 31,
                                                             ----------------------------------------
                                                               1998*      1997      1998*       1997
                                                            --------   --------   --------   --------
<S>                                                         <C>        <C>        <C>        <C>     

Revenue ..................................................  $ 33,102   $ 26,193   $ 98,149   $ 69,066
Cost of revenue ..........................................    15,545     11,898     43,648     30,465
                                                            --------   --------   --------   --------

   Gross profit ..........................................    17,557     14,295     54,501     38,601
                                                            --------   --------   --------   --------

Operating expenses:

   Research and development ..............................     6,624      3,757     17,897     10,761
   Purchased in-process research and development .........        --         --      6,100         --
   Marketing and sales ...................................     3,117      3,272     11,232      9,117
   General and administrative ............................     3,263      1,801      8,795      5,024
   Amortization of excess of net assets
    acquired over cost ...................................       (58)       (63)      (184)      (189)
                                                            --------   --------   --------   --------

Total operating expenses .................................    12,946      8,767     43,840     24,713
                                                            --------   --------   --------   --------

      Income from operations .............................     4,611      5,528     10,661     13,888

Interest income (expense), net ...........................       696        (14)     1,447        216
                                                            --------   --------   --------   --------

      Income before provision for income taxes and 
        equity in net earnings of affiliated companies ...     5,307      5,514     12,108     14,104

Provision for income taxes ...............................     1,737      1,851      4,117      4,791
                                                            --------   --------   --------   --------

      Income before equity in net earnings of
        affiliated companies .............................     3,570      3,663      7,991      9,313

Equity in net earnings of affiliated companies ...........       216        156        308        171
                                                            --------   --------   --------   --------

      Net income .........................................  $  3,786   $  3,819   $  8,299   $  9,484
                                                            --------   --------   --------   --------
                                                            --------   --------   --------   --------

Net income per share
      Basic ..............................................  $   0.34   $   0.45   $   0.81   $   1.12
                                                            --------   --------   --------   --------
                                                            --------   --------   --------   --------
      Diluted ............................................  $   0.33   $   0.43   $   0.78   $   1.07
                                                            --------   --------   --------   --------
                                                            --------   --------   --------   --------

Weighted average common and common
  share equivalents
        Basic ............................................    11,096      8,516     10,184      8,470
                                                            --------   --------   --------   --------
                                                            --------   --------   --------   --------
      Diluted ............................................    11,447      8,871     10,629      8,836
                                                            --------   --------   --------   --------
                                                            --------   --------   --------   --------
</TABLE>


                            * Restated - see note 9.


    The accompanying notes are an integral part of these unaudited condensed
                       consolidated financial statements.


                                       4
<PAGE>

                                 ADE CORPORATION
                 CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS
                            (in thousands; unaudited)

<TABLE>
<CAPTION>
                                                                 Nine months ended
                                                                     January 31,
                                                               ---------------------
                                                                 1998         1997
                                                               --------     --------
<S>                                                            <C>          <C>     

Cash flows provided by (used in) operating activities:
   Net income .............................................    $  8,299     $  9,484
   Adjustments to reconcile net income to
     net cash used in operating activities:
      Depreciation and amortization .......................       2,357        1,196
      Equity in net earnings of affiliated companies,
        net of dividends received .........................        (252)        (171)
      In-process research and development from
        business acquisition ..............................       6,100           --
      Deferred income taxes ...............................      (3,425)          --
      Changes in assets and liabilities:
        Accounts receivable, net ..........................      (3,616)      (5,710)
        Inventories .......................................      (6,386)      (9,634)
        Prepaid expenses and other current assets .........      (1,223)         (58)
        Accounts payable ..................................        (541)         347
        Accrued expenses ..................................        (133)        (718)
        Deferred income on sales to affiliate .............        (114)       3,662
        Income taxes payable ..............................      (1,915)          99
                                                               --------     --------

   Net cash used in operating activities ..................        (849)      (1,503)
                                                               --------     --------

Cash flows provided by (used in) investing activities:
   Purchases of fixed assets ..............................      (8,545)      (9,892)
   Change in restricted cash ..............................      (3,914)          --
   Equity investments and advances ........................        (190)      (2,563)
   Acquisition of business ................................     (10,048)          --
   Change in other assets .................................         (49)         (19)
                                                               --------     --------

   Net cash used in investing activities ..................     (22,746)     (12,474)
                                                               --------     --------

Cash flows provided by (used in) financing activities:
   Repayment of long-term debt ............................        (836)        (191)
   Proceeds from long-term debt ...........................       4,000        5,542
   Proceeds from common stock issuance, net of
     issuance costs .......................................      68,974          728
   Tax benefit related to the exercise of common
     stock options ........................................       1,379           --
                                                               --------     --------
   Net cash provided by financing activities ..............      73,517        6,079
                                                               --------     --------

Net increase (decrease) in cash and cash equivalents ......      49,922       (7,898)
Cash and cash equivalents, beginning of period ............      19,374       21,513
                                                               --------     --------

Cash and cash equivalents, end of period ..................    $ 69,296     $ 13,615
                                                               --------     --------
                                                               --------     --------
</TABLE>


    The accompanying notes are an integral part of these unaudited condensed
                       consolidated financial statements.


                                       5
<PAGE>

                                 ADE CORPORATION
                    NOTES TO UNAUDITED CONDENSED CONSOLIDATED
                              FINANCIAL STATEMENTS
         (in thousands, except share data and per share data; unaudited)


1. Basis of Preparation

The accompanying unaudited condensed consolidated financial statements of ADE
Corporation (the "Company") include, in the opinion of management, all
adjustments (consisting only of normal and recurring adjustments) necessary for
a fair statement of the Company's financial position as of January 31, 1998 and
the results of operations for the three and nine month periods ended January 31,
1998 and 1997. Results of operations for interim periods are not necessarily
indicative of those to be achieved for full fiscal years.

Pursuant to accounting requirements of the Securities and Exchange Commission
applicable to quarterly reports on Form 10-Q, the accompanying unaudited
condensed consolidated financial statements and these notes do not include all
disclosures required by generally accepted accounting principles for complete
financial statements. Accordingly, these statements should be read in
conjunction with the financial statements included in the Company's Annual
Report on Form 10-K for the fiscal year ended April 30, 1997.


2. Inventories

Inventories consist of the following:


<TABLE>
<CAPTION>

                                             January 31,   April 30,
                                                1998         1997
                                             -----------   ---------
                                             (unaudited)
        <S>                                    <C>          <C>    

        Raw materials and purchased parts .... $13,359      $ 9,867
        Work-in-process ......................  13,340       11,464
        Finished goods .......................   1,847          829
                                               -------      -------
                                               $28,546      $22,160
                                               -------      -------
                                               -------      -------

</TABLE>


3. Acquisition

On September 17, 1997 the Company acquired substantially all of assets of the
Semiconductor Solutions Division ("SSD") of LPA Software, Inc. in exchange for
$10,000 in cash and the assumption of certain liabilities. The Company also
incurred $48 in transaction costs related to the acquisition. SSD, which has
been integrated into the Company as ADE Yield Enhancement Solutions, provides
yield management and defect analysis software applications to the semiconductor
industry.

The acquisition has been accounted for under the purchase method. Accordingly,
the results of operations of SSD and the estimated fair market values of the
acquired assets and assumed liabilities have been included in the Company's
financial statements as of the date of the acquisition. Unaudited pro forma
results of operations presenting the acquisition as though it had been made at
the beginning of fiscal 1998 and fiscal 1997, respectively, including the
write-off of purchased 


                                       6
<PAGE>

                                 ADE CORPORATION
                    NOTES TO UNAUDITED CONDENSED CONSOLIDATED
                              FINANCIAL STATEMENTS
         (in thousands, except share data and per share data; unaudited)


in-process research and development, amortization of acquired intangible assets
and elimination of intercompany transactions, are as follows:

<TABLE>
<CAPTION>

                                         Three months ended              Nine months ended
                                            January 31,                    January 31,
                                         1998           1997           1998           1997
                                      ----------     ----------     ----------     -----------
<S>                                   <C>            <C>            <C>            <C>       

Revenue .........................     $   33,102     $   26,851     $   98,741     $   70,846
Net income ......................     $    3,786     $    3,622     $    7,740     $    4,920
Basic net income per share ......     $     0.34     $     0.43     $     0.76     $     0.58
Diluted net income per share ....     $     0.33     $     0.41     $     0.73     $     0.56

</TABLE>


The purchase price has been allocated to the acquired assets and assumed
liabilities as follows:

<TABLE>

<S>                                                             <C>    
 Property and equipment ...................................     $   354
 In-process research and development ......................       6,100
 Acquired software ........................................       1,100
 Assembled workforce ......................................         450
 Goodwill .................................................       2,403
 Current liabilities ......................................        (359)
                                                                --------
                                                                $10,048
                                                                --------
                                                                --------
</TABLE>


The amount allocated to in-process research and development was determined by an
independent appraiser and represented technology which had not reached
technological feasibility and had no alternative future use. Accordingly, this
amount of $6,100 was charged to operations at the acquisition date. The $2,403
allocated to goodwill and $450 allocated to assembled workforce are being
amortized on a straight line basis over their estimated useful lives of ten and
six years, respectively. The $1,100 allocated to acquired software is being
amortized at the greater of 1) the ratio that current gross revenue for the 
related products bear to total current and anticipated future gross revenue 
for those products or 2) on a straight-line basis over its estimated useful 
life of four years.


4. Long Term Debt

In December 1997, the Company issued a $4,000 tax-exempt Industrial Development
Bond through the Massachusetts Industrial Finance Agency. The bond carries an
interest rate of 5.79% per year, and provides for 50% of the principal to be
paid over 10 years from the date of issuance, with the remaining 50% due in
December, 2007. Monthly payments of principal and accrued interest for the bond
commence at $36 and decrease to $27 over the 10 year payment period. The
proceeds of the bond were used to fund the purchase and renovation of a
manufacturing facility at the Company's former headquarters site. The Company
secured the payments to be made under this bond with a cash deposit, which is
classified as restricted cash on the balance sheet.

In December 1997, the Company entered into an unsecured revolving line of credit
facility (the "Credit Facility") with a bank, which provides the Company the
option of borrowing at either the 


                                       7
<PAGE>

                                 ADE CORPORATION
                    NOTES TO UNAUDITED CONDENSED CONSOLIDATED
                              FINANCIAL STATEMENTS
         (in thousands, except share data and per share data; unaudited)


bank's prime rate or the bank's LIBOR rate plus 2%. The maximum borrowing under
the Credit Facility is $8,000 and is limited to a portion of the Company's
accounts receivable as defined in the agreement governing the Credit Facility.
The Credit Facility expires and all outstanding amounts thereunder are due on
December 21, 1999. Interest on outstanding borrowings is payable monthly in
arrears. Under the Credit Facility agreement, the Company is obligated to comply
with certain financial covenants. There were no borrowings outstanding at
January 31, 1998.


5. Capital Stock

In August 1997, the Company completed a public offering of 2,300,000 shares of
its common stock. The proceeds to the Company from the offering, net of offering
expenses, were $67,843.


6. Net Income Per Share

On November 1, 1997, the Company adopted Statement of Financial Accounting
Standards No. 128, "Earnings per Share" ("SFAS 128"), which establishes
standards for computing and presenting earnings per share. The new standard
replaces the presentation of earnings per share as prescribed in Accounting
Principles Board Opinion No. 15, "Earnings per Share", with a presentation of
basic and diluted earnings per share on the face of the statement of operations.
Basic earnings per share is computed by dividing income available to common
stockholders by the weighted average number of common shares outstanding for the
period. Diluted earnings per share is computed using the weighted average number
of common shares outstanding and gives effect to all dilutive potential common
shares outstanding during the period. Potential common shares outstanding
include shares issuable upon the assumed exercise of dilutive stock options
reflected under the treasury stock method.


7. Recently Issued Accounting Standards

In October, 1997, the Accounting Standards Executive Committee of the American
Institute of Certified Public Accountants issued Statement of Position ("SOP")
97-2, "Software Revenue Recognition." SOP 97-2 provides guidance on the timing
and amount of revenue recognition when licensing, selling, leasing or otherwise
marketing computer software. SOP 97-2 supersedes SOP 91-1 (also entitled
"Software Revenue Recognition") and is effective for transactions entered into
during fiscal years beginning after December 15, 1997. The Company will be
required to adopt SOP 97-2 for its fiscal year ending April 30, 1999. The
adoption of SOP 97-2 will not have a material effect on the Company's financial
position or it's results of operations.


                                       8
<PAGE>

8. Subsequent Event

In March 1998, the Company and its wholly owned subsidiary, Theta Acquisition
Corporation, entered into a merger agreement with Phase Shift Technology, Inc.
("PST"). The merger was completed in June 1998. Under the terms of the
agreement, the Company, through a wholly owned subsidiary, acquired all of the
outstanding shares of PST stock in exchange for 2,000,000 shares of ADE common
stock. PST is a privately held manufacturer of high performance, non-contact
surface metrology equipment located in Tucson, Arizona. PST products utilize
interferometric technology to monitor product yield and improve product design
and are currently used in the data storage, optics and related research
industries. The transaction has been accounted for as a pooling-of-interests and
qualifies as a tax-free reorganization.


9. Quarterly Results of Operations (Unaudited)

 JAL, the Company's 50% owned Japanese affiliate, recognizes revenue from 
product sales upon formal written acceptance by its customers. The Company 
recognizes revenue upon shipment of product and accrues for anticipated 
warranty costs at the time of shipment. This difference in revenue 
recognition policies resulted in the Company prematurely recognizing income 
on certain sales to its affiliate during fiscal 1998 for equipment installed 
at end-user customer locations but not formally accepted by customers. The 
Company has determined that its quarterly results of operations should be 
restated for the three and nine month periods ended January 31, 1998. Revenue 
of $1,237 and net income of $531 have been reversed for the three months 
ended January 31, 1998 to reflect these adjustments. In the opinion of 
management, all adjustments necessary to revise the quarterly financial 
statements have been recorded. Following is a summary of the unaudited 
quarterly results of operations for this quarter:

                                       9
<PAGE>

                                 ADE CORPORATION
                    NOTES TO UNAUDITED CONDENSED CONSOLIDATED
                              FINANCIAL STATEMENTS
         (in thousands, except share data and per share data; unaudited)

<TABLE>
<CAPTION>

                                                  3 months ended January 31, 1998

                                                                    As Previously
                                                   Restated           Reported
                                                   --------         -------------
<S>                                                <C>                <C>     

Revenue                                            $ 33,102           $ 34,339
Income from operations                                4,611              5,416
Net income                                            3,786              4,317
Net income per share - basic                       $   0.34           $   0.39
Net income per share - diluted                     $   0.33           $   0.38

</TABLE>

<TABLE>
<CAPTION>

                                                  9 months ended January 31, 1998

                                                                    As Previously
                                                   Restated           Reported
                                                   --------         -------------
<S>                                                <C>                <C>     

Revenue                                            $ 98,149           $ 99,386
Income from operations                               10,661             11,466
Net income                                            8,299              8,830
Net income per share - basic                       $   0.81           $   0.87
Net income per share - diluted                     $   0.78           $   0.83

</TABLE>


                                       10
<PAGE>

                                 ADE CORPORATION

         MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
                             RESULTS OF OPERATIONS

Introduction

ADE Corporation (the "Company") designs, manufactures, markets and services
highly precise, automated measurement, defect detection and handling equipment
with current applications in the production of semiconductor wafers,
semiconductor devices and computer disks.

On September 17, 1997, ADE Software Corporation, a wholly owned subsidiary of
the Company, acquired substantially all of the assets, and assumed certain
liabilities of the Semiconductor Solutions Division of LPA Software, Inc.
("SSD"), in exchange for $10 million in cash. The Company incurred $48,000 in
transaction costs related to the acquisition. SSD, located in Burlington,
Vermont, provides yield enhancement and defect analysis software applications to
the semiconductor industry and has been integrated into the Company as ADE Yield
Enhancement Solutions. A portion of the purchase price was allocated to
in-process research and development, which resulted in a charge to the Company's
operations of $6.1 million. In addition, $1.1 million was allocated to existing
software technology, which is being amortized based upon the ratio that current
gross revenue for the related products bear to the total anticipated gross
revenue for those products. The excess of the purchase price over the estimated
fair value of net assets acquired (goodwill) of approximately $2.4 million is
being amortized on a straight-line basis over a period of ten years. The
operating results of SSD have been included in the Company's results from the
date of acquisition.

In March 1998, the Company entered into a merger agreement with Phase Shift
Technology, Inc. ("PST"). The merger was completed in June, 1998. Under the
terms of the agreement, the Company, through a wholly owned subsidiary, acquired
all of the outstanding shares of PST stock in exchange for 2,000,000 shares of
ADE common stock. PST is a privately held manufacturer of high performance,
non-contact surface metrology equipment located in Tucson, Arizona. PST products
utilize interferometric technology to monitor product yield and improve product
design and are currently used in the data storage, optics and related research
industries. The transaction has been accounted for as a pooling-of-interests and
a tax-free reorganization.

The following information should be read in conjunction with the unaudited
condensed consolidated financial statements and notes thereto included in this
Quarterly Report and the audited consolidated financial statements and
Management's Discussion and Analysis of Financial Condition and Results of
Operations contained in the Company's Annual Report on Form 10-K for the fiscal
year ended April 30, 1997.


                                       11
<PAGE>

Results of Operations

Three Months Ended January 31, 1998 compared to Three Months Ended
January 31, 1997

Revenue increased 26.3% to $33.1 million in the third quarter of fiscal 1998
from $26.2 million in the third quarter of 1997. The increase was due to
increased unit sales of the Company's products. The increase in unit sales
resulted primarily from increased throughput in the Company's manufacturing
operations.

Gross margin decreased to 53.0% in the third quarter of fiscal 1998 from 54.6%
in the third quarter of 1997. This decrease resulted primarily from a higher
proportion of sales made through distributors in certain foreign markets. These
sales typically carry a lower unit selling price than domestic sales or sales
through external sales representatives. This decrease in selling price was
offset by lower commissions paid to sales representatives that resulted in
reduced sales and marketing expense. Additionally, the Company has increased its
worldwide customer service organization to support its higher levels of system
sales, with the related costs contributing to a lower overall gross margin.

Research and development expense increased 76.3% to $6.6 million in the third
quarter of fiscal 1998 from $3.8 million in the third quarter of 1997 and
increased as a percentage of revenue to 20.0% from 14.3% in the third quarter of
1997. New product development and product improvements have led to higher
research and development expenses through increased engineering resources and
higher project materials costs. A significant portion of the increase was
attributable to continuing efforts to complete development of the Company's
300mm surface inspection and wafer thickness measurement tools. The Company has
also continued development efforts to enhance its existing 200mm wafer and
advanced 200mm wafer systems. The Company is committed to increasing its
investment in research and development to maintain its position as a
technological leader.

Marketing and sales expense decreased 4.7% to $3.1 million in the third quarter
of fiscal 1998 from $3.3 million in the third quarter of 1997 and decreased as a
percentage of revenue to 9.4% from 12.5% in the third quarter of 1997. This
decrease occurred despite increases in the marketing and sales organization
required to support the Company's increased sales volume. The reduced period
expense resulted primarily from a lower proportion of sales and related sales
commissions made through external sales representatives in certain foreign
markets. The mix of sales channels through which the Company's products are sold
may have a significant impact on the Company's marketing and sales expense and
the results in any period may not be indicative of marketing and sales expense
for future periods.

General and administrative expenses increased 84.5% to $3.2 million in the third
quarter of fiscal 1998 versus $1.7 million in the third quarter of 1997 and
increased as a percentage of revenue to 9.9% from 6.9% in the third quarter of
1997. Expenses increased as the Company continued to develop management
infrastructure to support its rapid growth as well as amortization of the


                                       12
<PAGE>

goodwill that resulted from the September 1997 SSD acquisition included in the
third quarter of 1998.

Net interest income was $696,000 in the third quarter of fiscal 1998 compared to
net interest expense of $14,000 in the third quarter of 1997. The increase in
income resulted primarily from interest earned on the proceeds of a public
offering of the Company's common stock completed in August 1997 that raised
approximately $67.8 million in cash.

Nine Months Ended January 31, 1998 compared to Nine Months Ended
January 31, 1997

Revenue increased 42.1% to $98.1 million for the first nine months of fiscal
1998 from $69.1 million for the first nine months of 1997. The increase was due
to increased unit sales of the Company's products. The increase in unit sales
resulted primarily from stronger demand for capital equipment in the
semiconductor and computer disk drive industries.

Gross margin remained constant at 55.5% for the first nine months of fiscal 1998
versus 55.9% for the first nine months of 1997.

Research and development expense increased 66.3% to $17.9 million for the first
nine months of 1998 from $10.8 million for the first nine months of 1997, and
increased as a percentage of revenue to 18.2% from 15.6% for the first nine
months of 1997. Higher expenses resulted from increased engineering resources
and project materials utilized in new product development, including continuing
efforts to complete development of the Company's 300mm surface inspection and
wafer thickness measurement tools and improvements on current products aimed at
maintaining the Company's technological leadership.

Marketing and sales expense increased 23.2% to $11.2 million for the first nine
months of fiscal 1998 from $9.1 million for the first nine months of 1997, and
decreased as a percentage of revenue to 11.4% for the first nine months of
fiscal 1998 from 13.2% in 1997. The increase in expenses reflects the growth of
the marketing and sales organization to support the Company's increased sales
volume, with the decrease as a percentage of revenue reflecting growth in
expense at a slower rate than the overall increase in sales.

General and administrative expenses increased 78.1% to $8.6 million for the
first nine months of fiscal 1998 from $4.8 million for the first nine months of
1997 and increased as a percentage of revenue to 9.0% from 7.3% for the first
nine months of 1997. Expenses increased as the Company continued to develop
management infrastructure to support its rapid growth.

Net interest income was approximately $1.4 million for the first nine months of
fiscal 1998 compared to net interest income of $216,000 in the first nine months
of 1997. The increase in income resulted primarily from interest earned on the
proceeds of a public offering of the Company's common stock completed in August
1997, that raised approximately $67.8 million in cash.


                                       13
<PAGE>

Liquidity and Capital Resources

At January 31, 1998, the Company had $69.3 million in cash and cash equivalents
and $111.5 million in working capital. In addition, the Company had $3.9 million
in restricted cash as security for the tax-exempt Industrial Development Bond
("IDB") issued through the Massachusetts Industrial Finance Agency ("MIFA")
described below.

Net cash used by operating activities for the nine months ended January 31, 1998
was $849,000. Cash generated from operations, prior to increases in working
capital, was $9.4 million. This amount was comprised of net income of $8.3
million, non-cash charges for depreciation and amortization of $2.4 million and
purchased in-process research and development of $6.1 million. These amounts
were partially offset by a $3.4 million increase in deferred income tax
benefits, a $3.6 million increase in accounts receivable, a $114,000 decrease in
deferred income on sales to Japan ADE Ltd., the Company's 50% owned Japanese
distributor, and $252,000 of equity in earnings of affiliates, net of related
cash dividends received. The increase in deferred income tax benefits is
primarily due to the purchased in-process research and development charge of
$6.1 million, which is deductible over a fifteen year period for tax purposes.
Cash used for investments in working capital amounted to $10.2 million, which
consisted primarily of increased inventory and prepaid expenses of $6.9 million
and $1.2 million, respectively, and aggregate reductions in accounts payable and
accrued expenses of $683,000.

Cash used in investing activities consisted primarily of $8.5 million for
purchases of fixed assets, $10.0 million for the acquisition of the
Semiconductor Solutions Division of LPA Software, Inc. and $3.9 million in
restricted cash used to secure the December 1997 IDB described below. Included
in the fixed asset purchases was $4.5 million to purchase, refurbish and equip
the Company's former headquarters building in Newton, Massachusetts. This
facility will be used as headquarters for the Company's ADE Technologies, Inc.,
subsidiary, which manufactures equipment for the computer hard disk industry.

Cash provided by financing activities of $73.5 million consisted primarily of
$67.8 million received as the net proceeds of the public offering of the
Company's common stock completed in August 1997 and $4 million in proceeds from
the IDB issued through MIFA in December 1997. The bond carries an interest rate
of 5.79%, with 50% of the outstanding principal payable monthly on a ratable
basis for 10 years with the remaining 50% due in December 2007. The proceeds
from the IDB have been used to finance the purchase and renovation of a
manufacturing facility, with the related debt obligation secured by $3.9 million
of cash pledged by the Company as collateral. This cash is classified as
restricted cash on the January 31, 1998 balance sheet. Under the terms of the
bond agreement, the Company may substitute a letter of credit in an amount equal
to approximately 105% of the outstanding principal balance as collateral for the
Company's obligations under the IDB, allowing the restricted cash balance to be
used for general corporate purposes.

In December 1997, the Company entered into an unsecured revolving line of credit
facility (the "Credit Facility") with a bank, with a maximum borrowing amount of
$8 million. The Credit


                                       14
<PAGE>

Facility provides the Company the option of borrowing at either the bank's prime
rate or the bank's LIBOR rate plus 2%. The Credit Facility expires and all
outstanding amounts thereunder are due December 21, 1999. There were no
borrowings outstanding under the Credit Facility at January 31, 1998.

The Company expects to meet its near-term working capital needs and capital
expenditures primarily through cash generated from operations, its available
cash and cash equivalents and the above-referenced Credit Facility.

Year 2000

The Company has appointed a task force to assess the nature, extent and cost of
remediation of any Year 2000 compliance issues confronting the Company and its
suppliers. Such assessment has not yet been completed.

Other Risk Factors

In recent months there have been serious economic problems in the Far East. The
Company's business depends in large part upon the capital expenditures of
semiconductor wafer and device manufacturers, many of whom have operations in
the Far East. At January 31, 1998, the Company's backlog was $44.9 million,
which represents a reduction from fiscal year end 1997 and the first two
quarters of fiscal 1998. The Company anticipates that its revenue for the
current calendar year will be adversely affected by the conditions in the Asian
region, particularly Korea, which has historically accounted for a significant
portion of the Company's revenue base. Additionally, capital expenditures by
semiconductor wafer and device manufacturers historically have been cyclical as
they in turn depend upon the current and anticipated demand for integrated
circuits. Sustained periods of oversupply within the semiconductor industry
could adversely affect the performance of the Company.

Furthermore, the Company's success is dependent upon supplying technologically
superior products to the marketplace at appropriate times to satisfy customer
needs. Product development requires substantial investment and is subject to
technological risks. Delays or difficulties in product development could
adversely affect the performance of the Company.


                                       15
<PAGE>

                                    PART II.

                                OTHER INFORMATION

Item 1.    Legal Proceedings:

           None

Item 2.    Changes in Securities:

           None

Item 3.    Defaults Upon Senior Securities:

           None

Item 4.    ubmission of Matters to a Vote of Security Holders:

           None

Item 5.    Other Information:

           None

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

  a. See Exhibit Index, Page 18

  b. Reports on Form 8-K

     The Company filed a Current Report on Form 8-K with the Securities and
Exchange Commission on November 4, 1997. The Form 8-K reported that the Company
had purchased, through its wholly-owned subsidiary ADE Software Corporation, the
assets and assumed certain liabilities of the Semiconductor Solutions Division
("SSD") of LPA Software, Inc., a New York corporation for a cash purchase price
of $10,000,000.


                                       16
<PAGE>

                                   SIGNATURES

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.

ADE CORPORATION



Date: July 29, 1998                /s/ Mark D. Shooman
                                   -----------------------------
                                   Mark D. Shooman
                                   Vice President and Chief Financial Officer



Date: July 29, 1998                /s/ Robert C. Abbe
                                   ----------------------------
                                   Robert C. Abbe
                                   President and Chief Executive Officer


                                       17
<PAGE>

                                ADE CORPORATION

                                  EXHIBIT INDEX

<TABLE>
<CAPTION>

Exhibit                                                                    Page
-------                                                                    ----
<S>                                                                        <C>

   11  Statement Regarding Computation of Net Income per Share ..........    19

   27  Financial Data Schedule ..........................................

</TABLE>


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