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</LabelSeparator><Level>2</Level><ElementName>us-gaap_NatureOfOperations</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>terseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="D2012Q2YTD" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;div style="font-family:Times New Roman;font-size:10pt;"&gt;&lt;div style="line-height:120%;text-align:left;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;font-weight:bold;"&gt;Description of the Business&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;Spire Corporation ("Spire" or the "Company") develops, manufactures and markets highly-engineered products and services in two principal business areas: (i)&amp;#160;capital equipment and systems for the photovoltaic solar industry and (ii) biomedical, generally bringing to bear expertise in materials technologies, surface science and thin films across both business areas, discussed below.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;In the photovoltaic solar area, the Company develops, manufactures and markets specialized equipment for the production of terrestrial photovoltaic modules from solar cells and provide photovoltaic systems for grid connected applications in the commercial markets.&amp;#160;&amp;#160;The Company's equipment has been installed in approximately &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;200&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; factories in &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;50&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; countries.&amp;#160;&amp;#160;The equipment market is very competitive with major competitors located in the U.S., Japan and Europe.&amp;#160;&amp;#160;The Company's flagship product is its Sun Simulator which tests module performance.&amp;#160;&amp;#160;The Company's other product offerings include turn-key module lines and to a lesser extent other individual equipment.&amp;#160;&amp;#160;To compete the Company offers other services such as training and assistance with module certification.&amp;#160;&amp;#160;The Company also provides turn-key services to its customers to backward integrate to solar cell manufacturing.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;In the biomedical area, the Company provides value-added surface treatments to manufacturers of orthopedic and other medical devices that enhance the durability, antimicrobial characteristics or other material characteristics of their products; and performs sponsored research programs into practical applications of advanced biomedical and biophotonic technologies.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;On &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;March&amp;#160;9, 2012&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, the Company completed the sale of its semiconductor business unit, which provided semiconductor foundry services, operated a semiconductor foundry and fabrication facility and was engaged in the business of wafer epitaxy, foundry services, and device fabrication for the defense, medical, telecommunications and consumer products markets (the &amp;#8220;Semiconductor Business Unit&amp;#8221;), to Masimo Corporation ("Masimo").  Accordingly, the results of operations and assets and liabilities of the Semiconductor Business Unit are being presented herein as discontinued operations.  See Note 13 to the unaudited condensed consolidated financial statements.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;Operating results will depend upon revenue growth or decline and product mix, as well as the timing of shipments of higher priced products from the Company's solar equipment line and delivery of solar systems.&amp;#160;&amp;#160;Export sales, which amounted to &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;37%&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; and &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;34%&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; of net sales and revenues for the three and &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;six&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; months ended &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;30, 2013&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, respectively, and &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;65%&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; of net sales and revenues for both the three and &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;six&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; months ended &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;30, 2012&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, respectively, continue to constitute a significant portion of the Company's net sales and revenues.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;The Company has incurred operating losses from continuing operations.&amp;#160;&amp;#160;Operating loss from continuing operations was  &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$1.8 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; and &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$4.4 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; for the three and &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;six&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; months ended &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;30, 2013&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, respectively.  Operating loss from continuing operations was &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$1.8 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; and &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$3.4 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; for the three and &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;six&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; months ended &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;30, 2012&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, respectively.  Net cash used in operating activities was &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$1.9 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; for the &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;six&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; months ended &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;30, 2013&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, which includes &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$150 thousand&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; of cash used in operating activities of discontinued operations.  Net cash used in operating activities was &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$4.3 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; for the &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;six&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; months ended &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;30, 2012&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, which includes &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$1.7 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; of cash used in operating activities of discontinued operations.  As of &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;30, 2013&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, the Company had unrestricted cash and cash equivalents of &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$1.7 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; compared to &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$3.0 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; as of &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;December&amp;#160;31, 2012&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;.&amp;#160;&amp;#160;The maturity date of the Company's credit facilities is &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;August&amp;#160;30, 2013&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;.  These factors raise substantial doubt about the Company's ability to continue as a going concern.  The Company currently believes that its existing cash resources at &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;30, 2013&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, will be sufficient to fund its operations into the second half of 2013; however, the Company cannot assure you of this.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;The Company has various options on how to fund future operational losses or working capital needs, including but not limited to sales of equity, bank debt, the sale or license of assets and technology, or joint ventures involving cash infusions, as it has done in the past; however, there are no assurances that the Company will be able to sell equity, obtain or access bank debt, sell or license assets or technology or enter into such joint ventures on a timely basis and at appropriate values.&amp;#160;&amp;#160;The Company has developed several plans includ&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;ing potential strategic alternatives, cos&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;t reduction efforts and expanding revenue in other solar markets to offset a decline in business due to global economic conditions.&amp;#160;&amp;#160;The Company's inability to successfully implement its cost reduction strategies, expand revenue in other solar markets or to renew its credit facilities, could adversely impact the Company's ability to continue as a going concern.  &lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;Based on the forecasts and estimates underlying the Company's current operating plan, the financial statements do not include any adjustments that might be necessary if the Company is unable to continue as a going concern.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;/div&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for the nature of an entity's business, the major products or services it sells or provides and its principal markets, including the locations of those markets. If the entity operates in more than one business, the disclosure also indicates the relative importance of its operations in each business and the basis for the determination (for example, assets, revenues, or earnings).</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 275

 -SubTopic 10

 -Section 50

 -Paragraph 2

 -URI http://asc.fasb.org/extlink&amp;oid=6927468&amp;loc=d3e6003-108592



Reference 2: http://www.xbrl.org/2003/role/presentationRef

 -Publisher AICPA

 -Name Statement of Position (SOP)

 -Number 94-6

 -Paragraph 10

 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



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