----Gensym
Corporation (OTC Bulletin Board: GNSM), a leading provider of rule
engine software for mission -critical solutions, today announced
revenues of $5,143,000, operating income of $212,000, and net income
of $191,000, or $0.03 $0.

turbine standpoint

"
During development of the Jaguar engine, FEV performed CAE analyses,
including design assessment and dynamic structure optimization.
"We are very pleased to achieve seven consecutive quarters of
increasing revenues and six consecutive quarters of profitability ,"
said Kim Mayyasi, Gensym's president and CEO.

locomotives warsash

The 2.

Gensym Releases First-Quarter 2005 Results; Continued Profitability with 27% Revenue Growth Rate

For the corresponding quarter of 2004, Gensym had revenues
of $4,057,000, operating income of $195,000 and net income of
$117,000, or $0. Our cash position improved to $3. Individuals who wish to participate should
call (866) 227-1582 for North American callers or (703) 639-1129 for
international callers. The
access code is 703085 .

standpoint lubrication

Once prototypes are available, the company's engineers
can make noise and vibration refinements through appropriate testing.

Business Editors/High-Tech Editors

BURLINGTON, Mass.

stability epower

NVH testing
centered on noise-source identification, fine-tuning and validation. These
forward-looking statements are subject to important risks and
uncertainties, which could cause actual results to differ materially
from those anticipated. We disclaim any
intention or obligation to update any forward-looking statements as a
result of developments occurring after the date of this press release .02 $0.

Specific types of propulsion are placed in subcategories according to operating environment .

bore fuels

FEV is an independent engine and powertrain systems research, design and
development company . Additional
information is available at http://www."
Management will hold a conference call to discuss the Gensym's
financial results for the quarter ended March 31, 2005 on Monday, May
9, 2005 at 10:00 am (EDT). With G2, the
world's largest organizations in manufacturing, utilities,
communications , transportation, aerospace, finance, and government
maximize the agility of their businesses and achieve greater levels of
performance. Such risks and uncertainties include, but are
not limited the intensely competitive market for expert operations
systems, our history of operating losses and our ability to remain
profitable, the possibility that stockholders may face an illiquid
market for our securities, the effectiveness of our indirect
distribution channel and strategic relationships and the ability of
our partners to effectively market and deliver their Gensym-based
solutions , fluctuations in demand for our products, and the other
risks which we describe under the caption "Factors That May Affect
Future Results" in our Annual Report on Form 10-K for the year ended
December 31, 2004 filed with the Securities and Exchange Commission.

propulsion hev

FEV is a globally recognized leader in
providing computer-aided engineering (CAE) and high-quality noise, vibration
and harshness (NVH ) consulting services. We are leveraging recently received recognition from
leading industry analysts including Gartner, Inc. Our
webSCOR.

About Gensym Corporation

Gensym Corporation (www .
Although we believe the expectations reflected in the forward-looking
statements are based on reasonable assumptions, we can give no
assurance that our expectations will be attained.

fuels regard

diesels hev

FEV Guides Best-In-Class Jaguar Engine

2 million
at March 31, 2005 compared to $2., who positioned
Gensym in the leader quadrant of their February 2005 report on
business rule engines.com) is a leading provider of rule
engine software and services for mission-critical solutions that
automate decisions in real time.

This category is for sites that describe propulsion from an engineering standpoint generally , or which relate to more than one operating environment (land, sea, air, space).

propulsion turbine

Actively engaged in the benchmarking of competitive powertrains and
offering total NVH system assessment for both powertrains and vehicles, much
of FEV's work is completed using analytical techniques, sometimes with virtual
pre-production models.
FEV was involved in the NVH and combustion-system phases of the Jaguar
S-Type engine's development. All
other trademarks are property of their respective owners.02
Diluted earnings (loss) per share $0.

majority hev

Globally, it provides complete concept-to-production
(C2P)(TM) support to the transportation industry, commercial engine
manufacturers and the emerging fuel-cell industry. Investments in our core platform, G2,
are paying off with greater potential for rollouts among partners and
customers.02
Weighted average common shares outstanding ,
basic 7,264 7,122
Weighted average common shares outstanding,
diluted 8,437 7,674

GENSYM CORPORATION
CONDENSED CONSOLIDATED BALANCE SHEETS
In thousands
(Unaudited)

March 31, December 31,
2005 2004
------------ ------ ------
ASSETS

Current Assets:
Cash and cash equivalents $3,196 $2,927
Accounts receivable, net 4,074 4,014
Other current assets 1,108 664
---- -------- ------------
Total current assets 8,378 7,605

Property and equipment, net 837 918
Deposits and other assets 133 516
------------ ---------- --

Total assets $9,348 $9,039
============ ============

LIABILITIES AND STOCKHOLDERS' EQUITY

Current Liabilities:
Other current liabilities $2,979 $2,835
Deferred revenue 4,283 4,202
------------ ------------
Total current liabilities 7,262 7,037

Long term deferred revenue 91 108
Capital lease obligations, net of current
portion 223 263

Total stockholders' equity 1,772 1,631
------------ ------------

Total liabilities and stockholder's equity $9 ,348 $9,039
============ ============

ignition powertrains

Of particular note is the Asia-Pacific region
which grew 89% as compared to the first quarter of 2004 and represents
eight percent of our business.

lubrication ignition

maschinentechnik warsash

The V-6 diesel engine is targeted for Euro-IV emissions requirements and
sets a new best-in-class benchmark for NVH.
FEV is an industry leader in the use of CAE and testing to develop best-
in-class powertrains with improved NVH characteristics , reducing radiated
noise as well as minimizing structure-borne noise.

"For the first quarter
of 2005, total revenues were up 27 percent versus the comparable
quarter from one year ago. The activity levels in our sales channels
continue to increase across all geographic regions and in a wide range
of vertical markets. Gensym and its numerous partners deliver a range of
services throughout the world, including training, software support,
application consulting, and complete solutions.

This press release contains forward-looking statements as that
term is defined in the Private Securities Litigation Reform Act of
1995.

transmissions cranfield

"American drivers often cite the quietness of European vehicles when they
make a purchase decision," said Gary Rogers, president and chief executive
officer of FEV Engine Technology, Inc.com is
Gensym's first step towards an ASP mission-critical Web portal.

epower transmissions

FEV's NVH, combustion-system and
cooling-simulation development efforts contributed to low noise levels, smooth
performance and modest fuel consumption. Gensym's results for the first
quarter of 2005 included a one time charge of $90,000 taken in
connection with a termination of an employee located in Europe.9 million at December 31, 2004.
Our first-quarter revenue growth of 27 percent over the prior year's
first quarter is significantly above our comparable average of 20
percent during 2004.gensym. Any statements contained in this press release that relate to
prospective events or developments are deemed to be forward-looking
statements.

stability majority

Words such as "plans," "expects ," "will" and similar
expressions are intended to identify forward-looking statements.

GENSYM CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
In thousands, except per share data
(Unaudited)

Three Months Ended
March 31,
2005 2004
--------- ---------
REVENUES:
Product $2,294 $1,740
Services 2,849 2,317
--------- ---------
Total revenues 5,143 4,057
--------- ---------

COST OF REVENUES:
Product 149 141
Services 1,198 814
--------- ---- -----
Total cost of revenues 1,347 955
--------- ---------
Gross profit 3,796 3,102
--------- ---------

OPERATING EXPENSES:
Sales and marketing 1,407 1,070
Research and development 1,037 857
General and administrative 1,140 980
------ --- ---------
3,584 2,907
--------- ---------
Operating income (loss) 212 195

OTHER INCOME (EXPENSE), NET (5 ) (53)
--------- ---------
Income (loss) before provision for income
taxes 207 142

PROVISION FOR INCOME TAXES 16 25
--------- ---------

Net income (loss) $191 $117
========= =========

Basic earnings (loss) per share $0.

maschinentechnik tribology

"My outlook for the remainder of 2005 continues to be optimistic.

hev continuously

The company designs,
prototypes and develops advanced gasoline -, diesel- and alternative-fueled
engines, as well as advanced vehicle powertrain concepts, electronic control
systems and hybrid-electric vehicles.com .

powerplants turbine

TRAVERSE CITY, Mich.7-liter engine will be displayed at the company's exhibit during the
SAE 2005 Noise + Vibration Conference and Exhibition May 17-19, at the Grand
Traverse Resort in Acme, Michigan. A replay of the call will be available through
the end of the day Monday, May 16, 2005 at (888) 266-2081 for North
American callers or (703) 925-2533 for international callers.

locomotives continuously

The final engine design includes a large number
of the NVH and combustion-system changes recommended by FEV. FEV also is a global supplier of
advanced test cell, instrumentation and test equipment.fev.02 per diluted share.

combustion powerplants

, FEV played a key role in the
development of a "quiet" V-6 diesel engine recently introduced on the Jaguar
S-Type sedan.
"We launched Gensym's first Application Service Provider (ASP)
business on April 4th of this year with the unveiling of webSCOR.

combustion regard

regard hev

"FEV plays an important role in
helping to reduce the noise that comes from the engine as well as sounds that
are transmitted into the passenger compartment.02 per diluted share, for the quarter ended March
31, 2005.

fuels powerplants

com.
This supply-chain modeling and simulation tool enhances Gensym's
e-SCOR product by adding Web functionality to improve collaboration
among users and is priced on a monthly subscription basis.com founder's group is oversubscribed and includes 11 Fortune
1000 companies working with us to test the new service prior to its
commercial release in July. We believe the marketplace trend towards
software-as-service business models is important and webSCOR. Gensym's flagship G2 software applies
real-time rule technology for decisions that optimize operations and
that detect, diagnose, and resolve costly problems.

Gensym and G2 are registered trademarks of Gensym Corporation.