7 Other raw materials utilized by the Company include nylon, polyethylene resin and compounds and plasticizers, fluoropolymer compounds, optical fiber and a variety of filling, binding and sheathing materials. The Company believes that all of these materials are available in suf ficient quantities through purchases in the open market. Patents and T rademarks The Company believes that the success of its business depends more on the technical competence, creativity and marketing abilities of its employees rather than on any individual patent, trademark or copyright. Nonetheless, the Company has a policy of seeking patents when appropriate on inventions concerning new products and product improvements as part of its ongoing research, development and manufacturing activities. The Company owns numerous patents and trademarks globally , with pending applications for additional patents and trademarks, and maintains trade secret protection for certain confidential and proprietary information. Although in the aggregate these patents are of considerable importance to the manufacturing and marketing of many of the Company's products, the Company does not consider any single patent to be material to its business as a whole. The Company considers PDIC related trademarks and trade names to be of material value to our business including Phelps Dodge International Corporation ® and the PDIC global symbols. Other trademarks, which are considered to be generally important are General Cable ® , Anaconda ® , BICC ® , Carol ® , GenSpeed ® , Helix/HiT emp ® , NextGen ® , Silec ® , Polyrad ® and the Company's triad symbol. The Company believes that products bearing these trademarks have achieved significant brand recognition within the industry . Seasonality The Company generally has experienced and expects to continue to experience certain seasonal trends in many products in which demand is linked with construction spending. Demand for these products during winter months in certain geographies is usually lower than demand during spring and summer months. Therefore, lar ger amounts of working capital are generally required during winter months in order to build inventories in anticipation of higher demand during the spring and summer months, when construction activity increases. In turn, receivables related to higher sales activity during the spring and summer months are generally collected during the fourth quarter of the year . Additionally , the Company has historically experienced changes in demand resulting from poor or unusual weather . Competition The markets for all of the Company's products are highly competitive and most markets include several competitors. The degree of competition varies by operating segment and product line. However , in general, the industry is mature and cost driven. Although the primary competitive factors for the Company's products vary somewhat across the dif ferent product categories, the principal factors influencing competition include, but are not limited to, price, quality , breadth of product line, inventory , delivery time, customer service, the environmental impact of the products, and the ability to meet the customer's needs. Many of the Company's products are made to industry specifications, and are therefore functionally interchangeable with those of competitors. However , the Company believes that significant opportunities exist to dif ferentiate all of its products on the basis of quality , consistent availability , conformance to manufacturer's specifications and customer service. The Company believes its competitive strengths include breadth of product line, brand recognition, distribution and logistics, strong customer relations, operating ef ficiency and commitment to quality control and continuous improvement. Advertising Expense Advertising expense consists of expenses relating to promoting the Company’ s products, including trade shows, catalogs, and e- commerce promotions, and is char ged to expense when incurred. Advertising expense was $ 10.7 million , $1 1.2 million and $12.0 million in 2012 , 201 1 and 2010 , respectively . Envir onmental Matters The Company is subject to a variety of federal, state, local and foreign laws and regulations covering the storage, handling, emission and dischar ge of materials into the environment, including CERCLA, the Clean W ater Act, the Clean Air Act (including the 1990 amendments) and the Resource Conservation and Recovery Act. While it is dif ficult to estimate future environmental liabilities accurately , the Company does not currently anticipate any material adverse ef fect on its consolidated results of operations, financial position or cash flows as a result of compliance with federal, state, local or foreign environmental laws or regulations or remediation costs of the sites as discussed below in Item 3 - Legal Proceedings and Note 18 - Commitments and Contingencies. Employees At December 31, 2012 , General Cable employed approximately 14,000 employees worldwide. Approximately 38% of our employees were covered by collective bar gaining agreements, of which 55% are subject to agreements that expire within one year of December 31, 2012 . The Company believes it will successfully renegotiate these contracts as they come due. Generally , labor T able of Contents